Download - Teradata Oracle® Database Gateway for User's Guide · 1 Introduction to the Oracle Database Gateway for Teradata Overview of the Oracle Database Gateway for Teradata 1-1 About Heterogeneous

Oracle® Database Gateway forTeradataUser's Guide

19cE96407-01April 2019

Oracle Database Gateway for Teradata User's Guide, 19c

E96407-01

Copyright © 2002, 2019, Oracle and/or its affiliates. All rights reserved.

Primary Author: Rhonda Day

Contributing Authors: Vira Goorah, Juan Pablo Ahues-Vasquez, Peter Castro, Charles Benet, Peter Wong,Govind Lakkoju

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Contents

Preface

Audience ix

Documentation Accessibility ix

Related Documents x

Conventions x

1 Introduction to the Oracle Database Gateway for Teradata

Overview of the Oracle Database Gateway for Teradata 1-1

About Heterogeneous Services Technology 1-1

About Oracle Database Gateway for Teradata 1-2

2 Teradata Gateway Features and Restrictions

Remote Insert Rowsource 2-1

Using the Pass-Through Feature 2-2

Executing Stored Procedures and Functions 2-2

Return Values and Stored Procedures 2-3

Result Sets and Stored Procedures 2-3

OCI Program Fetching from Result Sets in Sequential Mode 2-5

PL/SQL Program Fetching from Result Sets in Sequential Mode 2-6

CHAR Semantics 2-7

Multi-byte Character Sets Ratio Suppression 2-7

IPv6 Support 2-7

Gateway Session IDLE Timeout 2-8

Database Compatibility Issues for Teradata 2-8

Schema Considerations 2-8

Naming Rules 2-8

Rules for Naming Objects 2-8

Case Sensitivity 2-9

Data Types 2-9

Binary Literal Notation 2-10

Data Type Conversion 2-10

iii

Queries 2-10

Row Selection 2-10

Empty Bind Variables 2-11

Locking 2-11

Known Restrictions 2-11

Transactional Integrity 2-11

Transaction Capability 2-12

COMMIT or ROLLBACK in PL/SQL Cursor Loops Closes Open Cursors 2-12

Pass-Through Feature 2-12

Bind Variables for Date Columns 2-12

SQL Syntax 2-13

WHERE CURRENT OF Clause 2-13

CONNECT BY Clause 2-13

ROWID 2-13

EXPLAIN PLAN Statement 2-13

SQL*Plus 2-13

Database Links 2-13

Known Problems 2-14

Teradata LONG VARCHAR Data Type 2-14

Schema Names and PL/SQL 2-14

Data Dictionary Views and PL/SQL 2-15

3 Case Studies

Case Descriptions 3-1

Installation Media Contents 3-1

Demonstration Files 3-2

Demonstration Requirements 3-2

Creating Demonstration Tables 3-2

Demonstration Table Definitions 3-3

Demonstration Table Contents 3-3

Case 1: Simple Queries 3-4

Case 2: A More Complex Query 3-4

Case 3: Joining Teradata Tables 3-4

Case 4: Write Capabilities 3-5

DELETE Statement 3-5

UPDATE Statement 3-5

INSERT Statement 3-5

Case 5: Data Dictionary Query 3-5

Case 6: The Pass-Through Feature 3-5

UPDATE Statement 3-5

iv

SELECT Statement 3-6

A Data Type Conversion

B Supported SQL Syntax and Functions

Supported SQL Statements B-1

DELETE B-1

INSERT B-1

SELECT B-2

UPDATE B-2

Oracle Functions B-2

Functions Not Supported by Teradata B-2

Functions Supported by Teradata B-2

Arithmetic Operators B-3

Comparison Operators B-3

Group Functions B-3

String Functions B-3

Other Functions B-3

C Data Dictionary

Teradata System Catalog Tables C-1

Accessing the Gateway Data Dictionary C-1

Direct Queries to Teradata Tables C-2

Supported Views and Tables C-2

Data Dictionary Mapping C-3

Default Column Values C-4

Gateway Data Dictionary Descriptions C-4

ALL_CATALOG C-4

ALL_COL_COMMENTS C-4

ALL_CONS_COLUMNS C-5

ALL_CONSTRAINTS C-5

ALL_IND_COLUMNS C-6

ALL_INDEXES C-6

ALL_OBJECTS C-8

ALL_TAB_COLUMNS C-9

ALL_TAB_COMMENTS C-10

ALL_TABLES C-10

ALL_USERS C-11

ALL_VIEWS C-12

v

DBA_CATALOG C-12

DBA_COL_COMMENTS C-12

DBA_OBJECTS C-13

DBA_TAB_COLUMNS C-13

DBA_TAB_COMMENTS C-14

DBA_TABLES C-15

DICT_COLUMNS C-16

DICTIONARY C-16

DUAL C-17

USER_CATALOG C-17

USER_COL_COMMENTS C-17

USER_CONS_COLUMNS C-17

USER_CONSTRAINTS C-18

USER_IND_COLUMNS C-18

USER_INDEXES C-19

USER_OBJECTS C-20

USER_TAB_COLUMNS C-21

USER_TAB_COMMENTS C-22

USER_TABLES C-22

USER_USERS C-24

USER_VIEWS C-24

D Initialization Parameters

Initialization Parameter File Syntax D-1

Oracle Database Gateway for Teradata Initialization Parameters D-2

HS_DB_DOMAIN D-3

HS_DB_INTERNAL_NAME D-4

HS_DB_NAME D-4

HS_DESCRIBE_CACHE_HWM D-4

HS_LANGUAGE D-4

Character Sets D-5

Language D-5

Territory D-5

HS_LONG_PIECE_TRANSFER_SIZE D-6

HS_OPEN_CURSORS D-6

HS_RPC_FETCH_REBLOCKING D-6

HS_RPC_FETCH_SIZE D-7

HS_TIME_ZONE D-7

HS_TRANSACTION_MODEL D-7

IFILE D-8

vi

HS_FDS_TIMESTAMP_MAPPING D-8

HS_FDS_DATE_MAPPING D-9

HS_FDS_CONNECT_INFO D-9

HS_FDS_DEFAULT_OWNER D-9

HS_FDS_TRANSACTION_ISOLATION D-10

HS_FDS_PROC_IS_FUNC D-10

HS_FDS_RECOVERY_ACCOUNT D-11

HS_FDS_RECOVERY_PWD D-11

HS_FDS_TRACE_LEVEL D-11

HS_FDS_TRANSACTION_LOG D-12

HS_FDS_FETCH_ROWS D-12

HS_IDLE_TIMEOUT D-12

HS_NLS_LENGTH_SEMANTICS D-12

HS_KEEP_REMOTE_COLUMN_SIZE D-13

HS_FDS_REMOTE_DB_CHARSET D-13

HS_FDS_SUPPORT_STATISTICS D-14

HS_FDS_ARRAY_EXEC D-14

Index

vii

List of Tables

A-1 Data Type Mapping and Restrictions A-1

C-1 Oracle Data Dictionary View Names and Teradata Equivalents C-3

C-2 ALL_CATALOG C-4

C-3 ALL_COL_COMMENTS C-4

C-4 ALL_CONS_COLUMNS C-5

C-5 ALL_CONSTRAINTS C-5

C-6 ALL_IND_COLUMNS C-6

C-7 ALL_INDEXES C-6

C-8 ALL_OBJECTS C-8

C-9 ALL_TAB_COLUMNS C-9

C-10 ALL_TAB_COMMENTS C-10

C-11 ALL_TABLES C-10

C-12 ALL_USERS C-11

C-13 ALL_VIEWS C-12

C-14 DBA_CATALOG C-12

C-15 DBA_COL_COMMENTS C-12

C-16 DBA_OBJECTS C-13

C-17 DBA_TAB_COLUMNS C-13

C-18 DBA_TAB_COMMENTS C-14

C-19 DBA_TABLES C-15

C-20 DICT_COLUMNS C-16

C-21 DICTIONARY C-16

C-22 DUAL C-17

C-23 USER_CATALOG C-17

C-24 USER_COL_COMMENTS C-17

C-25 USER_CONS_COLUMNS C-17

C-26 USER_CONSTRAINTS C-18

C-27 USER_IND_COLUMNS C-18

C-28 USER_INDEXES C-19

C-29 USER_OBJECTS C-20

C-30 USER_TAB_COLUMNS C-21

C-31 USER_TAB_COMMENTS C-22

C-32 USER_TABLES C-22

C-33 USER_USERS C-24

C-34 USER_VIEWS C-24

viii

Preface

This manual describes the Oracle Database Gateway for Teradata, which enablesOracle client applications to access Teradata data through Structured QueryLanguage (SQL). The gateway, with the Oracle database, creates the appearance thatall data resides on a local Oracle database, even though the data can be widelydistributed.

This preface covers the following topics:

• Audience

• Documentation Accessibility

• Related Documents

• Conventions

AudienceThis manual is intended for Oracle database administrators who perform the followingtasks:

• Installing and configuring the Oracle Database Gateway for Teradata

• Diagnosing gateway errors

• Using the gateway to access Teradata data

Note:

You should understand the fundamentals of Oracle Database Gatewaysand the UNIX based platforms before using this guide to install oradminister the gateway.

Documentation AccessibilityFor information about Oracle's commitment to accessibility, visit the OracleAccessibility Program website at http://www.oracle.com/pls/topic/lookup?ctx=acc&id=docacc.

Access to Oracle Support

Oracle customers that have purchased support have access to electronic supportthrough My Oracle Support. For information, visit http://www.oracle.com/pls/topic/lookup?ctx=acc&id=info or visit http://www.oracle.com/pls/topic/lookup?ctx=acc&id=trsif you are hearing impaired.

ix

http://www.oracle.com/pls/topic/lookup?ctx=acc&id=docacc

http://www.oracle.com/pls/topic/lookup?ctx=acc&id=docacc

http://www.oracle.com/pls/topic/lookup?ctx=acc&id=info

http://www.oracle.com/pls/topic/lookup?ctx=acc&id=info

http://www.oracle.com/pls/topic/lookup?ctx=acc&id=trs

Related DocumentsFor more information, see these Oracle resources:

• Oracle Database New Features Guide

• Oracle Call Interface Programmer's Guide

• Oracle Database Administrator's Guide

• Oracle Database Development Guide

• Oracle Database Concepts

• Oracle Database Performance Tuning Guide

• Oracle Database Error Messages

• Oracle Database Globalization Support Guide

• Oracle Database Reference

• Oracle Database SQL Language Reference

• Oracle Database Net Services Administrator's Guide

• SQL*Plus User's Guide and Reference

• Oracle Database Heterogeneous Connectivity User's Guide

• Oracle Database Security Guide

ConventionsThe following text conventions are used in this document:

Convention Meaning

boldface Boldface type indicates graphical user interface elements associatedwith an action, or terms defined in text or the glossary.

italic Italic type indicates book titles, emphasis, or placeholder variables forwhich you supply particular values.

monospace Monospace type indicates commands within a paragraph, URLs, codein examples, text that appears on the screen, or text that you enter.

Preface

x

1Introduction to the Oracle DatabaseGateway for Teradata

Oracle Database Gateways provide the ability to transparently access data residing ina non-Oracle system from an Oracle environment. The following topics briefly coversHeterogeneous Services, the technology that the Oracle Database Gateway forTeradata is based on.

To get a good understanding of generic gateway technology, Heterogeneous Services,and how Oracle Database Gateways fit in the picture, reading the Oracle DatabaseHeterogeneous Connectivity User's Guide first is highly recommended.

Topics:

• Overview

• Heterogeneous Services Technology

• Oracle Database Gateways

Overview of the Oracle Database Gateway for TeradataHeterogeneous data access is a problem that affects a lot of companies. A lot ofcompanies run several different database systems. Each of these systems stores dataand has a set of applications that run against it. Consolidation of this data in onedatabase system is often hard - in large part because many of the applications that runagainst one database may not have an equivalent that runs against another. Until suchtime as migration to one consolidated database system is made feasible, it isnecessary for the various heterogeneous database systems to interoperate.

Oracle Database Gateways provide the ability to transparently access data residing ina non-Oracle system from an Oracle environment. This transparency eliminates theneed for application developers to customize their applications to access data fromdifferent non-Oracle systems, thus decreasing development efforts and increasing themobility of the application. Applications can be developed using a consistent Oracleinterface for both Oracle and Teradata.

Gateway technology is composed of two parts: a component that has the generictechnology to connect to a non-Oracle system, which is common to all the non-Oraclesystems, called Heterogeneous Services, and a component that is specific to the non-Oracle system that the gateway connects to. Heterogeneous Services, in conjunctionwith the Oracle Database Gateway agent, enables transparent access to non-Oraclesystems from an Oracle environment.

About Heterogeneous Services TechnologyHeterogeneous Services provides the generic technology for connecting to non-Oraclesystems. As an integrated component of the database, Heterogeneous Services canexploit features of the database, such as the powerful SQL parsing and distributedoptimization capabilities.

1-1

Heterogeneous Services extend the Oracle SQL engine to recognize the SQL andprocedural capabilities of the remote non-Oracle system and the mappings required toobtain necessary data dictionary information. Heterogeneous Services provides twotypes of translations: the ability to translate Oracle SQL into the proper dialect of thenon-Oracle system as well as data dictionary translations that displays the metadata ofthe non-Oracle system in the local format. For situations where no translations areavailable, native SQL can be issued to the non-Oracle system using the pass-throughfeature of Heterogeneous Services.

Heterogeneous Services also maintains the transaction coordination between Oracleand the remote non-Oracle system, such as providing the two-phase commit protocolto ensure distributed transaction integrity, even for non-Oracle systems that do notnatively support two-phase commit.

See Also:

Oracle Database Heterogeneous Connectivity User's Guide for moreinformation about Heterogeneous Services.

About Oracle Database Gateway for TeradataThe capabilities, SQL mappings, data type conversions, and interface to the remotenon-Oracle system are contained in the gateway. The gateway interacts withHeterogeneous Services to provide the transparent connectivity between Oracle andnon-Oracle systems.

The gateway must be installed on a machine running either the Teradata database orthe Teradata client. This machine can be the same machine as the Oracle database oron the same machine as the Teradata database or on a third machine as astandalone. Each configuration has its advantages and disadvantages. The issues toconsider when determining where to install the gateway are network traffic, operatingsystem platform availability, hardware resources and storage.

Chapter 1About Oracle Database Gateway for Teradata

1-2

2Teradata Gateway Features andRestrictions

After the gateway is installed and configured, you can use the gateway to accessTeradata data, pass Teradata commands from applications to the Teradata database,perform distributed queries, and copy data.

Topics:

• Remote Insert Rowsource

• Using the Pass-Through Feature

• Executing Stored Procedures and Functions

• CHAR Semantics

• Multi-byte Character Sets Ratio Suppression

• IPv6 Support

• Gateway Session IDLE Timeout

• Database Compatibility Issues for Teradata

• Known Restrictions

• Known Problems

Remote Insert RowsourceA remote insert rowsource feature allows remote insert requiring local Oracle data towork through the Oracle database and Oracle Database Gateway. This functionalityrequires that the Oracle database and the Oracle Database Gateway to be version12.2 or later.

By Oracle Database design, some distributed statement must be executed at thedatabase link site. But in certain circumstances, there is data needed to execute thesequeries that must be fetched from the originating Oracle Database. Underhomogeneous connections, the remote Oracle database would call back the sourceOracle database for such data. But in heterogeneous connections, this is not viable,because this means that the Foreign Data Store would have to query call backfunctions, or data, that can only be provided by the Oracle instance that issued thequery. In general, these kinds of statements are not something that can be supportedthrough the Oracle Database Gateway.

The following categories of SQL statements results in a callback:

• Any DML with a sub-select, which refers to a table in Oracle database.

• Any DELETE, INSERT, UPDATE or "SELECT... FOR UPDATE..." SQL statementcontaining SQL functions or statements that needs to be executed at theoriginating Oracle database.

2-1

These SQL functions include USER, USERENV, and SYSDATE; and involve theselection of data from the originating Oracle database.

• Any SQL statement that involves a table in Oracle database, and a LONG or LOBcolumn in a remote table.

An example of a remote INSERT statement that can work through the remote insertrowsource feature is as follows:

INSERT INTO gateway_table@gateway_link select * from local_table;

Using the Pass-Through FeatureThe gateway can pass Teradata commands or statements from the application directlyto the Teradata database using the DBMS_HS_PASSTHROUGH package.

Use the DBMS_HS_PASSTHROUGH package in a PL/SQL block to specify the statement tobe passed to the Teradata database, as follows:

DECLARE num_rows INTEGER;BEGIN num_rows := DBMS_HS_PASSTHROUGH.EXECUTE_IMMEDIATE@TERA('command');END;/

Where command cannot be one of the following:

• BEGIN TRANSACTION

• BT

• COMMIT

• END TRANSACTION

• ET

• ROLLBACK

The DBMS_HS_PASSTHROUGH package supports passing bind values and executingSELECT statements.

See Also:

Oracle Database PL/SQL Packages and Types Reference and Chapter 3,Features of Oracle Database Gateways, of Oracle Database HeterogeneousConnectivity User's Guide for more information about theDBMS_HS_PASSTHROUGH package.

Executing Stored Procedures and FunctionsUsing the procedural feature, the gateway can execute stored procedures that aredefined in the Teradata database. It is not necessary to relink the gateway or definethe procedure to the gateway, but the procedure's access privileges must permitaccess by the gateway.

Chapter 2Using the Pass-Through Feature

2-2

Standard PL/SQL statements are used to execute a stored procedure.

The gateway supports stored procedures in three mutually exclusive modes:

• Normal mode: Have access to IN/OUT arguments only

• Return value mode: Have a return value for all stored procedures

• Resultset mode: Out values are available as last result set

Return Values and Stored ProceduresBy default, all stored procedures and functions do not return a return value to the user.To enable return values, set the HS_FDS_PROC_IS_FUNC parameter in the initializationparameter file.

See Also:

Initialization Parameters for information about both editing the initializationparameter file and the HS_FDS_PROC_IS_FUNC parameter.

Note:

If you set the HS_FDS_PROC_IS_FUNC gateway initialization parameter, youmust change the syntax of the procedure execute statement for all existingstored procedures.

In the following example, the employee name JOHN SMYTHE is passed to the Teradatastored procedure REVISE_SALARY. The stored procedure retrieves the salary value fromthe Teradata database to calculate a new yearly salary for JOHN SMYTHE. The revisedsalary returned in RESULT is used to update EMP in a table of an Oracle database:

DECLARE INPUT VARCHAR2(15); RESULT NUMBER(8,2);BEGIN INPUT := 'JOHN SMYTHE'; RESULT := REVISE_SALARY@TERA(INPUT); UPDATE EMP SET SAL = RESULT WHERE ENAME =: INPUT;END;/

The procedural feature automatically converts non-Oracle data types to and fromPL/SQL data types.

Result Sets and Stored ProceduresThe Oracle Database Gateway for Teradata provides support for stored procedureswhich return result sets.

Chapter 2Executing Stored Procedures and Functions

2-3

By default, all stored procedures and functions do not return a result set to the user.To enable result sets, set the HS_FDS_RESULTSET_SUPPORT parameter in theinitialization parameter file.

See Also:

Initialization Parameters for information about both editing the initializationparameter file and the HS_FDS_RESULTSET_SUPPORT parameter. For furtherinformation about Oracle support for result sets in non-Oracle databases see Oracle Database Heterogeneous Connectivity User's Guide.

Note:

If you set the HS_FDS_RESULTSET_SUPPORT gateway initialization parameter,you must change the syntax of the procedure execute statement for allexisting stored procedures or errors will occur.

When accessing stored procedures with result sets through the Oracle DatabaseGateway for Teradata, you will be in the sequential mode of Heterogeneous Services.

The Oracle Database Gateway for Teradata returns the following information toHeterogeneous Services during procedure description:

• All the input arguments of the remote stored procedure

• None of the output arguments

• One out argument of type ref cursor (corresponding to the first result set returnedby the stored procedure)

Client programs have to use the virtual package functiondbms_hs_result_set.get_next_result_set to get the ref cursor for subsequent resultsets. The last result set returned is the out argument from the procedure.

The limitations of accessing result sets are the following:

• Result sets returned by a remote stored procedure have to be retrieved in theorder in which they were placed on the wire

• On execution of a stored procedure, all result sets returned by a previouslyexecuted stored procedure will be closed (regardless of whether the data hasbeen completely

In the following example, the Teradata stored procedure is executed to fetch thecontents of the emp and dept tables from Teradata:

CREATE PROCEDURE refcurproc (@arg1 varchar(255), @arg2 varchar(255) output)ASSECLECT @arg2 = @arg1SELECT * FROM EMPSELECT * FROM DEPTGO


2-4

This stored procedure assigns the input parameter arg1 to the output parameter arg2,opens the query SELECT * FROM EMP in ref cursor rc1, and opens the query SELECT *FROM DEPT in ref cursor rc2.

Note:

Chained mode must be set before creating the stored procedure. Issue thefollowing command in Teradata: set chained on

OCI Program Fetching from Result Sets in Sequential ModeThe following example shows OCI program fetching from result sets in sequentialmode:

OCIEnv *ENVH;OCISvcCtx *SVCH;OCIStmt *STMH;OCIError *ERRH;OCIBind *BNDH[3];OraText arg1[20];OraText arg2[255];OCIResult *rset;OCIStmt *rstmt;ub2 rcode[3];ub2 rlens[3];sb2 inds[3];OraText *stmt = (OraText *) "begin refcurproc@TERA(:1,:2,:3); end;";OraText *n_rs_stm = (OraText *) "begin :ret := DBMS_HS_RESULT_SET.GET_NEXT_RESULT_SET@TERA; end;";

/* Prepare procedure call statement */

/* Handle Initialization code skipped */OCIStmtPrepare(STMH, ERRH, stmt, strlen(stmt), OCI_NTV_SYNTAX, OCI_DEFAULT);

/* Bind procedure arguments */inds[0] = 0;strcpy((char *) arg1, "Hello World");rlens[0] = strlen(arg1);OCIBindByPos(STMH, &BNDH[0], ERRH, 1, (dvoid *) arg1, 20, SQLT_CHR, (dvoid *) &(inds[0]), &(rlens[0]), &(rcode[0]), 0, (ub4 *) 0, OCI_DEFAULT);inds[1] = -1;OCIBindByPos(STMH, &BNDH[1], ERRH, 1, (dvoid *) arg2, 20, SQLT_CHR, (dvoid *) &(inds[1]), &(rlens[1]), &(rcode[1]), 0, (ub4 *) 0, OCI_DEFAULT);

inds[2] = 0;rlens[2] = 0;OCIDescriptorAlloc(ENVH, (dvoid **) &rset, OCI_DTYPE_RSET, 0, (dvoid **) 0);OCIBindByPos(STMH, &BNDH[2], ERRH, 2, (dvoid *) rset, 0, SQLT_RSET, (dvoid *) &(inds[2]), &(rlens[2]), &(rcode[2]), 0, (ub4 *) 0, OCI_DEFAULT);

/* Execute procedure */OCIStmtExecute(SVCH, STMH, ERRH, 1, 0, (CONST OCISnapshot *) 0, (OCISnapshot *) 0, OCI_DEFAULT);


2-5

/* Convert result set to statement handle */OCIResultSetToStmt(rset, ERRH);rstmt = (OCIStmt *) rset;

/* After this the user can fetch from rstmt *//* Issue get_next_result_set call to get handle to next_result set *//* Prepare Get next result set procedure call */

OCIStmtPrepare(STMH, ERRH, n_rs_stm, strlen(n_rs_stm), OCI_NTV_SYNTAX, OCI_DEFAULT);

/* Bind return value */OCIBindByPos(STMH, &BNDH[1], ERRH, 1, (dvoid *) rset, 0, SQLT_RSET, (dvoid *) &(inds[1]), &(rlens[1]), &(rcode[1]), 0, (ub4 *) 0, OCI_DEFAULT);

/* Execute statement to get next result set*/OCIStmtExecute(SVCH, STMH, ERRH, 1, 0, (CONST OCISnapshot *) 0, (OCISnapshot *) 0, OCI_DEFAULT);

/* Convert next result set to statement handle */OCIResultSetToStmt(rset, ERRH);rstmt = (OCIStmt *) rset;

/* Now rstmt will point to the second result set returned by theremote stored procedure */

/* Repeat execution of get_next_result_set to get the output arguments */

PL/SQL Program Fetching from Result Sets in Sequential ModeAssume that the table loc_emp is a local table exactly like the Teradata emp table. Thesame assumption applies for loc_dept. outargs is a table with columns correspondingto the out arguments of the Teradata stored procedure.

create or replace package rcpackage is type RCTYPE is ref cursor;end rcpackage;/

declare rc1 rcpackage.rctype; rec1 loc_emp%rowtype; rc2 rcpackage.rctype; rec2 loc_dept%rowtype; rc3 rcpackage.rctype; rec3 outargs%rowtype; out_arg varchar2(255);

begin

-- Execute procedure out_arg := null; refcurproc@TERA('Hello World', out_arg, rc1);

-- Fetch 20 rows from the remote emp table and insert them into loc_emp for i in 1 .. 20 loop fetch rc1 into rec1; insert into loc_emp (rec1.empno, rec1.ename, rec1.job, rec1.mgr, rec1.hiredate, rec1.sal, rec1.comm, rec1.deptno);


2-6

end loop;

-- Close ref cursor close rc1;

-- Get the next result set returned by the stored procedure rc2 := dbms_hs_result_set.get_next_result_set@TERA;

-- Fetch 5 rows from the remote dept table and insert them into loc_dept for i in 1 .. 5 loop fetch rc2 into rec2; insert into loc_dept values (rec2.deptno, rec2.dname, rec2.loc); end loop;

--Close ref cursor close rc2;

-- Get the output arguments from the remote stored procedure -- Since we are in sequential mode, they will be returned in the -- form of a result set rc3 := dbms_hs_result_set.get_next_result_set@TERA;

-- Fetch them and insert them into the outarguments table fetch rc3 into rec3; insert into outargs (rec3.outarg, rec3.retval);

-- Close ref cursor close rc3;

end;/

CHAR SemanticsThis feature allows the gateway to optionally run in CHAR Semantics mode. Rather thanalways describing Teradata CHAR columns as CHAR(n BYTE), this feature describesthem as CHAR(n CHAR) and VARCHAR(n CHAR). The concept is similar to Oracledatabase CHAR Semantics. You need to specify HS_NLS_LENGTH_SEMANTICS=CHAR toactivate this option. Refer to Initialization Parameters for more detail.

Multi-byte Character Sets Ratio SuppressionThis feature optionally suppresses the ratio expansion from Teradata database toOracle databases involving a multi-byte character set (for example, from US7ASCII toAL32UTF8, or from KO16MSWIN949 to KO16KSC5601). By default, Oracle gatewaysassume the worst ratio to prevent data being truncated or allocation of buffer withinsufficient size. However, if you have specific knowledge of your Teradata databaseand do not want the expansion to occur, you can specifyHS_KEEP_REMOTE_COLUMN_SIZE parameter to suppress the expansion. Refer to Initialization Parameters for more detail.

IPv6 SupportBesides full IPv6 support between Oracle databases and the gateway, IPv6 is alsosupported between this gateway and Teradata. Refer to HS_FDS_CONNECT_INFOparameter in Initialization Parameters for more detail.

Chapter 2CHAR Semantics

2-7

Gateway Session IDLE TimeoutYou can optionally choose to terminate long idle gateway sessions automatically withthe gateway parameter HS_IDLE_TIMEOUT. Specifically, when a gateway session is idlefor more than the specified time limit, the gateway session is terminated with anypending changes rolled back.

Database Compatibility Issues for TeradataTeradata and Oracle databases function differently in some areas, causingcompatibility problems. The compatibility issues are described in the following links:

• Schema Considerations

• Naming Rules

• Data Types

• Queries

• Locking

Schema ConsiderationsThe Oracle concept of a schema does not exist in Teradata. A schema name includedin a query is recognized by Teradata as a database name. In the Oracle database, theschema of an object is identical to the owner of that object. However, when oneretrieves or references an OWNER field in a Data Dictionary view such as ALL_TABLES,the OWNER field really is referencing a Teradata database name.

When querying data dictionary tables, the following results are returned:

• ALL_* data dictionary tables, data for every Teradata database is returned. TheTeradata database name is returned in the OWNER, INDEX_OWNER, or TABLE_OWNERcolumn depending on the data dictionary table being referenced.

• ALL_USERS data dictionary table, each Teradata database name is returned in theUSERNAME column.

• USER_* data dictionary tables, data for the default Teradata database is returnedfor the OWNER or TABLE_OWNER column depending on the data dictionary table beingreferenced. If a default Teradata database is not defined, the DBC Teradatasystem database is used.

Naming RulesNaming rule issues include the following:

• Rules for Naming Objects

• Case Sensitivity

Rules for Naming ObjectsOracle and Teradata use different database object naming rules. For example, themaximum number of characters allowed for each object name can be different. Also,

Chapter 2Gateway Session IDLE Timeout

2-8

the use of single and double quotation marks, case sensitivity, and the use ofalphanumeric characters can all be different.

Case SensitivityThe Oracle database defaults to uppercase unless you surround identifiers with doublequote characters. For example, to refer to the Teradata table called emp, enter thename with double quote characters, as follows:

SQL> SELECT * FROM "emp"@TERA;

However, to refer to the Teradata table called emp in the Teradata database namedScott from an Oracle application, enter the following:

SQL> SELECT * FROM "Scott"."emp"@TERA;

If the Teradata table called emp in the Teradata database named SCOTT, a nameconsisting entirely of uppercase letters, you can enter the owner name without doublequote characters, as follows:

SQL> SELECT * FROM SCOTT."emp"@TERA;

or

SQL> SELECT * FROM scott."emp"@TERA;

Oracle recommends that you surround all Teradata object names with double quotecharacters and use the exact letter case for the object names as they appear in theTeradata data dictionary. This convention is not required when referring to thesupported Oracle data dictionary tables or views listed in Data Dictionary.

If existing applications cannot be changed according to these conventions, createviews in Oracle to associate Teradata names to the correct letter case. For example,to refer to the Teradata table emp from an existing Oracle application by using onlyuppercase names, define the following view:

SQL> CREATE VIEW EMP (EMPNO, ENAME, SAL, HIREDATE) AS SELECT "empno", "ename", "sal", "hiredate" FROM "emp"@TERA;

With this view, the application can issue statements such as the following:

SQL> SELECT EMPNO, ENAME FROM EMP;

Using views is a workaround solution that duplicates data dictionary informationoriginating in the Teradata data dictionary. You must be prepared to update the Oracleview definitions whenever the data definitions for the corresponding tables arechanged in the Teradata database.

Data TypesData type issues include the following:

• Binary Literal Notation

• Data Type Conversion

Chapter 2Database Compatibility Issues for Teradata

2-9

Binary Literal NotationOracle SQL uses hexadecimal digits surrounded by single quotes to express literalvalues being compared or inserted into columns defined as data type RAW.

This notation is not converted to syntax compatible with the Teradata VARBINARY andBINARY data types (a ff surrounded by single quotes followed by hexadecimal digits).

For example, the following statement is not supported:

SQL> INSERT INTO BINARY_TAB@TERA VALUES ('ff'xb)

where BINARY_TAB contains a column of data type VARBINARY or BINARY. Use bindvariables when inserting into or updating VARBINARY and BINARY data types.

Data Type ConversionTeradata does not support implicit date conversions. Such conversions must beexplicit.

For example, the gateway issues an error for the following SELECT statement:

SELECT DATE_COL FROM TEST@TERA WHERE DATE_COL = "1-JAN-2001";

To avoid problems with implicit conversions, add explicit conversions, as in thefollowing:

SELECT DATE_COL FROM TEST@TERA WHERE DATE_COL = TO_DATE("1-JAN-2001")

See Also:

Data Type Conversion for more information about restrictions on data types.

QueriesQuery issues include the following:

• Row Selection

• Empty Bind Variables

Row SelectionTeradata evaluates a query condition for all selected rows before returning any of therows. If there is an error in the evaluation process for one or more rows, no rows arereturned even though the remaining rows satisfy the condition.

Oracle evaluates the query condition row-by-row and returns a row when theevaluation is successful. Rows are returned until a row fails the evaluation.

Chapter 2Database Compatibility Issues for Teradata

2-10

Empty Bind VariablesFor VARCHAR bind variables, the gateway passes empty bind variables to the Teradatadatabase as a NULL value.

LockingThe locking model for an Teradata database differs significantly from the Oraclemodel. The gateway depends on the underlying Teradata behavior, so the followingpossible scenarios can affect Oracle applications that access Teradata through thegateway:

• Read access might block write access.

• Write access might block read access.

• Statement-level read consistency is not guaranteed.

See Also:

Teradata documentation for information about the Teradata lockingmodel.

Known RestrictionsIf you encounter incompatibility problems not listed in this section or in "KnownProblems", contact Oracle Support Services. The following topics describe the knownrestrictions and includes suggestions for dealing with them when possible:

• Transactional Integrity

• Transaction Capability

• COMMIT or ROLLBACK in PL/SQL Cursor Loops Closes Open Cursors

• Pass-Through Feature

• Bind Variables for Date Columns

• SQL Syntax

• SQL*Plus

• Database Links

Transactional IntegrityThe gateway cannot guarantee transactional integrity in the following cases:

• When a statement that is processed by the gateway causes an implicit commit inthe target database

• When the target database is configured to work in autocommit mode

Chapter 2Known Restrictions

2-11

Note:

Oracle strongly recommends the following:

– If you know that executing a particular statement causes an implicitcommit in the target database, then ensure that this statement isexecuted in its own transaction.

– Do not configure the target database to work in autocommit mode.

Transaction CapabilityThe gateway does not support savepoints. If a distributed update transaction is underway involving the gateway and a user attempts to create a savepoint, the followingerror occurs:

ORA-02070: database dblink does not support savepoint in this context

By default, the gateway is configured as COMMIT_CONFIRM and it is always the commitpoint site when the Teradata database is updated by the transaction.

COMMIT or ROLLBACK in PL/SQL Cursor Loops Closes OpenCursors

Any COMMIT or ROLLBACK issued in a PL/SQL cursor loop closes all open cursors, whichcan result in the following error:

ORA-1002: fetch out of sequence

To prevent this error, move the COMMIT or ROLLBACK statement outside the cursor loop.

Pass-Through FeatureOracle recommends that you place a DDL statement in its own transaction whenexecuting such a statement with the pass-through feature. An explicit COMMIT must beissued after the DDL statement.

If the SQL statements being passed through the gateway result in an implicit commit atthe Teradata database, the Oracle transaction manager is unaware of the commit andan Oracle ROLLBACK command cannot be used to roll back the transaction.

Bind Variables for Date ColumnsYou cannot compare columns of data type TIME or TIMESTAMP to a bind variable.

The following SQL statement causes an error message:

SQL> select time_column from time_table@TERA where time_column = :a;

The following error is issued:

Invalid operation on an ANSI Datetime or Interval value.


2-12

SQL SyntaxRestrictions on SQL syntax are listed as follows:

• WHERE CURRENT OF Clause

• CONNECT BY Clause

• ROWID

• EXPLAIN PLAN Statement

See Also:

Supported SQL Syntax and Functions for more information about restrictionson SQL syntax.

WHERE CURRENT OF ClauseUPDATE and DELETE statements with the WHERE CURRENT OF clause are not supportedby the gateway because they rely on the Oracle ROWID implementation. To update ordelete a specific row through the gateway, a condition style WHERE clause must beused.

CONNECT BY ClauseThe gateway does not support the CONNECT BY clause in a SELECT statement.

ROWIDThe Oracle ROWID implementation is not supported.

EXPLAIN PLAN StatementThe EXPLAIN PLAN statement is not supported.

SQL*PlusYou need to use double quotes to wrap around lowercase table names.

For example:

copy from tkhouser/tkhouser@inst1 insert loc_tkhodept using select * from "tkhodept"@TERA;

Database LinksThe gateway is not a shared server process and cannot support shared databaselinks. Each gateway session spawns a separate gateway process and connectionscannot be shared.


2-13

Known ProblemsThis section describes known problems and includes suggestions for correcting themwhen possible. If you have any questions or concerns about the problems, contactOracle Support Services. A current list of problems is available online. Contact yourlocal Oracle office for information about accessing the list.

The known problems are as follows:

• Teradata LONG VARCHAR Data Type

• Schema Names and PL/SQL

• Data Dictionary Views and PL/SQL

Teradata LONG VARCHAR Data TypeThe following restrictions apply when using LONG VARCHAR data types:

• An unsupported SQL function cannot be used in a SQL statement that accesses acolumn defined as Teradata data type LONG VARCHAR.

• You cannot use SQL*Plus to select data from a column defined as Teradata datatype LONG VARCHAR when the data is greater than 80 characters in length. Oraclerecommends using Pro*C or Oracle Call Interface to access such data in aTeradata database.

• LONG VARCHAR data types must be NULLABLE for INSERT or UPDATE to work.

• A table including a LONG VARCHAR column must have a unique index defined on thetable or the table must have a separate column that serves as a primary key.

• LONG VARCHAR data cannot be read through pass-through queries.

The gateway does not support the PL/SQL function COLUMN_VALUE_LONG of theDBMS_SQL package.

See Also:

Supported SQL Syntax and Functions for more information about restrictionson SQL syntax.

Schema Names and PL/SQLIf you do not prefix a Teradata database object with its schema name in a SQLstatement within a PL/SQL block, the following error message occurs:

ORA-6550 PLS-201 Identifier table_name must be declared.

Change the SQL statement to include the schema name of the object.

Chapter 2Known Problems

2-14

Data Dictionary Views and PL/SQLYou cannot refer to data dictionary views in SQL statements that are inside a PL/SQLblock.

Chapter 2Known Problems

2-15

3Case Studies

The following case studies for Teradata demonstrate some of the features of theOracle Database Gateway. You can verify that the gateway is installed and operatingcorrectly by using the demonstration files included on the distribution media.

The demonstration files are automatically copied to disk when the gateway is installed.

Topics:

• Case Descriptions

• Installation Media Contents

• Demonstration Files

• Demonstration Requirements

• Creating Demonstration Tables

• Case 1: Simple Queries

• Case 2: A More Complex Query

• Case 3: Joining Teradata Tables

• Case 4: Write Capabilities

• Case 5: Data Dictionary Query

• Case 6: The Pass-Through Feature

Case DescriptionsThe cases illustrate:

• A simple query (Case 1)

• A more complex query (Case 2)

• Joining Teradata tables (Case 3)

• Write capabilities (Case 4)

• A data dictionary query (Case 5)

• The pass-through feature (Case 6)

Installation Media ContentsThe distribution media contains the following:

• Demonstration files.

• One SQL script file that creates the demonstration tables in the Teradatadatabase.

3-1

• One SQL script file that drops the demonstration tables from the Teradatadatabase.

Demonstration FilesAfter a successful gateway installation, use the demonstration files stored in thedirectory $ORACLE_HOME/dg4tera/demo where $ORACLE_HOME is the directory underwhich the gateway is installed. The directory contains the following demonstration files:

• bldtera.sql

• case1.sql

• case2.sql

• case3.sql

• case4a.sql

• case4b.sql

• case4c.sql

• case5.sql

• case6a.sql

• case6b.sql

• droptera.sql

Demonstration RequirementsThe case studies assume these requirements have been met:

• The gateway demonstration tables are installed in the Teradata database.

• The Oracle database has an account named SCOTT with a password of TIGER.

• The Oracle database has a database link called GTWLINK (set up as public orprivate to the user SCOTT) that connects the gateway to a Teradata database asSCOTT with password TIGER2.

For example, you can create the database link as follows:

SQL> CREATE DATABASE LINK GTWLINK CONNECT TO SCOTT 2 IDENTIFIED BY TIGER2 USING 'GTWSID';

• Oracle Net Services is configured correctly and running.

Creating Demonstration TablesThe case studies are based on the GTW_EMP, GTW_DEPT, and GTW_SALGRADE tables. If thedemonstration tables have not been created in the Teradata database, use the bldtera.sql script to create them.

The script creates the demonstration tables in the Teradata database accordingly:

CREATE TABLE GTW_EMP (EMPNO SMALLINT NOT NULL ENAME VARCHAR(10),JOB VARCHAR(9),

Chapter 3Demonstration Files

3-2

MGR SMALLINT,HIREDATE DATETIME,SAL NUMERIC(7,2),COMM NUMERIC(7,2),DEPTNO SMALLINT)CREATE TABLE GTW_DEPT (DEPTNO SMALLINT NOT NULL,DNAME VARCHAR(14),LOC VARCHAR(13)) CREATE TABLE GTW_SALGRADE (GRADE REAL,LOSAL NUMERIC(9,4),HISAL NUMERIC(9,4))

Demonstration Table DefinitionsThe table definitions are listed here using information retrieved by the SQL*PLUSDESCRIBE command:

GTW_EMP

Name Null? Type------------------------------- -------- ----EMPNO NOT NULL NUMBER(5)ENAME VARCHAR2(10)JOB VARCHAR2(9)MGR NUMBER(5)HIREDATE DATESAL NUMBER(7,2)COMM NUMBER(7,2)DEPTNO NUMBER(5)

GTW_DEPT

Name Null? Type------------------------------- -------- ----DEPTNO NOT NULL NUMBER(5)DNAME VARCHAR2(14)LOC VARCHAR2(13)

GTW_SALGRADE

Name Null? Type------------------------------- -------- ----GRADE FLOAT(53)LOSAL NUMBER(9,4)HISAL NUMBER(9,4)

Demonstration Table ContentsThe contents of the Teradata tables are:

GTW_EMP

EMPNO ENAME JOB MGR HIREDATE SAL COMM DEPTNO----- ----- --- --- -------- --- ---- ------7369 SMITH CLERK 7902 17-DEC-80 800 207499 ALLEN SALESMAN 7698 20-FEB-81 1600 300 307521 WARD SALESMAN 7698 22-FEB-81 1250 500 307566 JONES MANAGER 7839 02-APR-81 2975 20

Chapter 3Creating Demonstration Tables

3-3

7654 MARTIN SALESMAN 7698 28-SEP-81 1250 1400 307698 BLAKE MANAGER 7839 01-MAY-81 2850 307782 CLARK MANAGER 7839 09-JUN-81 2450 107788 SCOTT ANALYST 7566 09-DEC-82 3000 207839 KING PRESIDENT 17-NOV-81 5000 107844 TURNER SALESMAN 7698 08-SEP-81 1500 0 307876 ADAMS CLERK 7788 12-JAN-83 1100 207900 JAMES CLERK 7698 03-DEC-81 950 307902 FORD ANALYST 7566 03-DEC-81 3000 207934 MILLER CLERK 7782 23-JAN-82 1300 10

GTW_DEPT

DEPTNO DNAME LOC ----- -------------- -------- 10 ACCOUNTING NEW YORK 20 RESEARCH DALLAS 30 SALES CHICAGO 40 OPERATIONS BOSTON

GTW_SALGRADE

GRADE LOSAL HISAL------ ------ ----- 1 700 1200 2 1201 1400 3 1401 2000 4 2001 3000 5 3001 9999

Case 1: Simple QueriesCase 1 demonstrates the following:

• A simple query.

• A simple query retrieving full date information.

The first query retrieves all the data from GTW_DEPT and confirms that the gateway isworking correctly.

Case 2: A More Complex QueryCase 2 demonstrates the following:

• The functions SUM(expression) and NVL(expr1, expr2) in the SELECT list.

• The GROUP BY and HAVING clauses.

This query retrieves the departments from GTW_EMP whose total monthly expenses arehigher than $10,000.

Case 3: Joining Teradata TablesCase 3 demonstrates the following:

• Joins between Teradata tables.

• Subselects.

Chapter 3Case 1: Simple Queries

3-4

The query retrieves information from three Teradata tables and relates the employeesto their department name and salary grade, but only for those employees earningmore than the average salary.

Case 4: Write CapabilitiesCase 4 is split into three cases and demonstrates the following:

• DELETE Statement

• UPDATE Statement

• INSERT Statement

DELETE StatementCase 4a demonstrates bind values and subselect. All employees in department 20 andone employee, WARD, in department 30 are deleted.

UPDATE StatementCase 4b provides an example of a simple UPDATE statement. In this example,employees are given a $100 a month salary increase.

INSERT StatementCase 4c is an example of a simple insert statement that does not provide informationfor all columns.

Case 5: Data Dictionary QueryCase 5 demonstrates data dictionary mapping. It retrieves all the tables and views thatexist in the Teradata database that begin with "GTW".

Case 6: The Pass-Through FeatureCase 6 demonstrates the gateway pass-through feature that allows an application tosend commands or statements to Teradata.

This case demonstrates:

• A pass-through UPDATE statement using bind variables.

• A pass-through SELECT statement.

UPDATE StatementCase 6a provides an example of a pass-through UPDATE statement with bind variables.In this example, the salary for EMPNO 7934 is set to 4000.

Chapter 3Case 4: Write Capabilities

3-5

SELECT StatementCase 6b provides an example of a pass-through SELECT statement. The data that isreturned from the SELECT statement is inserted into a local table at the Oracledatabase.

Chapter 3Case 6: The Pass-Through Feature

3-6

AData Type Conversion

The gateway converts Teradata data types to Oracle data types as follows:

Table A-1 Data Type Mapping and Restrictions

Teradata Oracle Criteria If Oracle uses large varchar (32k)

BLOB LONG RAW

BYTE RAW -

BYTEINT NUMBER(3) BYTEINT range is -128 to +127

CHAR CHAR -

CHAR CHARACTERSET UNICODE

CHAR -

CLOB LONG

DATE CHAR(10) -

DECIMAL NUMBER(p[,s]) -

FLOAT FLOAT(24) with precision <= single precisionfloat

FLOAT FLOAT(53) with precision > single precisionfloat

INTEGER NUMBER(10) NUMBER range is -2,147,483,648to 2,147,483,647

INTERVAL CHAR -

LONG VARCHARCHARACTER SETUNICODE

LONG if Oracle DB Character Set =Unicode. Otherwise, it is notsupported.

LONG VARCHAR LONG if Oracle DB Character Set =Unicode. Otherwise, it is notsupported

SMALLINT NUMBER(5) NUMBER range is -32768 to 32767

TIME CHAR(15) -

TIMESTAMP DATE -

VARBYTE RAW 1 < = N < = 2000 1 <= N <= 32767

VARBYTE LONG RAW 2000 < N N < 32767

VARCHAR VARCHAR2

LONG

N < = 4000

4000 < N

N <= 32767

32767 < N

VARCHAR()CHARACTER SETUNICO

NVARCHAR2 N < = 2000

4000 < N

A-1

BSupported SQL Syntax and Functions

The following topics describe supported SQL Syntax and Functions:

• Supported SQL Statements

• Oracle Functions

Supported SQL StatementsWith a few exceptions, the gateway provides full support for Oracle DELETE, INSERT,SELECT, and UPDATE statements.

The gateway does not support Oracle data definition language (DDL) statements. Noform of the Oracle ALTER, CREATE, DROP, GRANT, or TRUNCATE statements can be used.Instead, use the pass-through feature of the gateway if you need to use DDLstatements against the Teradata database.

See Also:

Oracle Database SQL Language Reference for detailed descriptions ofkeywords, parameters, and options.

DELETEThe DELETE statement is fully supported. However, only Oracle functions supported byTeradata can be used.

See Also:

"Functions Supported by Teradata" for a list of supported functions.

INSERTThe INSERT statement is fully supported. However, only Oracle functions supported byTeradata can be used.

See Also:


B-1

SELECTThe SELECT statement is fully supported, with these exceptions:

• CONNECT BY condition

• NOWAIT

• START WITH condition

• WHERE CURRENT OF

UPDATEThe UPDATE statement is fully supported. However, only Oracle functions supported byTeradata can be used. Also, you cannot have SQL statements in the subquery thatrefer to the same table name in the outer query. Subqueries are not supported in theSET clause.

See Also:


Oracle FunctionsAll functions are evaluated by the Teradata database after the gateway has convertedthem to Teradata SQL.

Functions Not Supported by TeradataOracle SQL functions with no equivalent function in Teradata are not supported in DELETE, INSERT, or UPDATE statements, but are evaluated by the Oracle database if thestatement is a SELECT statement. That is, the Oracle database performs post-processing of SELECT statements sent to the gateway.

If an unsupported function is used in a DELETE, INSERT, or UPDATE, statement, thefollowing Oracle error occurs:

ORA-02070: database db_link_name does not support function in this context

Functions Supported by TeradataThe gateway translates the following Oracle database functions in SQL statements totheir equivalent Teradata functions:

• Arithmetic Operators

• Comparison Operators

• Group Functions

• String Functions

Appendix BOracle Functions

B-2

• Other Functions

Arithmetic Operators

Oracle Teradata

+ +

- -

* *

/ /

Comparison Operators

Oracle Teradata

= =

> >

< <

>= >=

<= <=

<>, !=, ^= <>, !=

IS NOT NULL IS NOT NULL

IS NULL IS NULL

Group Functions

Oracle Teradata

AVG AVG

COUNT COUNT

MAX MAX

MIN MIN

SUM SUM

String Functions

Oracle Teradata

INSTR POSITION

Other Functions

Oracle Teradata

ABS ABS


B-3

Oracle Teradata

EXP EXP

LOG(a, b) LOG10(b) / LOG10(a)

POWER **

SQRT SQRT


B-4

CData Dictionary

The Oracle Database Gateway for Teradata User's Guide translates a query thatrefers to an Oracle database data dictionary table into a query that retrieves the datafrom Teradata system catalog tables. You perform queries on data dictionary tablesover the database link in the same way you query data dictionary tables in the Oracledatabase. The gateway data dictionary is similar to the Oracle database datadictionary in appearance and use.

Topics:

• Data Dictionary Mapping

• Gateway Data Dictionary Descriptions

Teradata System Catalog TablesTeradata data dictionary information is stored in the Teradata database as Teradatasystem catalog tables. The Teradata system catalog tables define the structure of adatabase. When you change data definitions, Teradata reads and modifies theTeradata system catalog tables to add information about the user tables.

Accessing the Gateway Data DictionaryAccessing a gateway data dictionary table or view is identical to accessing a datadictionary in an Oracle database. You issue a SQL SELECT statement specifying adatabase link. The Oracle database data dictionary view and column names are usedto access the gateway data dictionary in an Oracle database. Synonyms of supportedviews are also acceptable. For example, the following statement queries the datadictionary table ALL_CATALOG to retrieve all table names in the Teradata database:

SQL> SELECT * FROM ALL_CATALOG@TERA;

When a data dictionary access query is issued, the gateway:

1. Maps the requested table, view, or synonym to one or more Teradata system tablenames. The gateway translates all data dictionary column names to theircorresponding Teradata database column names within the query. Refer to "DataDictionary Mapping" for details.

2. Sends the translated query to Teradata.

3. Might convert the retrieved Teradata data to give it the appearance of the Oracledatabase data dictionary table.

4. Passes the data dictionary information from the translated Teradata systemcatalog table to the Oracle database.

C-1

Note:

The values returned when querying the gateway data dictionary mightnot be the same as the ones returned by the Oracle Enterprise ManagerDESCRIBE command.

Direct Queries to Teradata TablesQueries issued directly to individual Teradata system catalog tables are allowed butthey return different results because the Teradata system catalog table column namesdiffer from those of the data dictionary view. Also, certain columns in a Teradatasystem catalog table cannot be used in data dictionary processing.

Supported Views and TablesThe gateway supports the following views and tables:

Supported Views and Tables Supported Views and Tables

ALL_CATALOG ALL_COL_COMMENTS

ALL_CONS_COLUMNS ALL_CONSTRAINTS

ALL_IND_COLUMNS ALL_INDEXES

ALL_OBJECTS ALL_TAB_COLUMNS

ALL_TAB_COMMENTS ALL_TABLES

ALL_USERS ALL_VIEWS

DBA_CATALOG DBA_COL_COMMENTS

DBA_OBJECTS DBA_TABLES

DBA_TAB_COLUMNS DBA_TAB_COMMENTS

DICT_COLUMNS DICTIONARY

DUAL USER_COL_COMMENTS

USER_CATALOG USER_CONSTRAINTS

USER_CONS_COLUMNS USER_INDEXES

USER_IND_COLUMNS USER_TAB_COLUMNS

USER_OBJECTS USER_TABLES

USER_TAB_COMMENTS USER_VIEWS

USER_USERS

No other Oracle database data dictionary tables or views are supported. If you use aview not on the list, you receive the Oracle database error code for no more rowsavailable.

Queries through the gateway of any data dictionary table or view beginning with ALL_can returns rows from the Teradata database even when access privileges for thoseTeradata objects have not been granted. When querying an Oracle database with the

Appendix CDirect Queries to Teradata Tables

C-2

Oracle data dictionary, rows are returned only for those objects you are permitted toaccess.

Data Dictionary MappingThe table in this section lists Oracle data dictionary view names and the equivalentTeradata system tables used. A plus sign (+) indicates that a join operation is involved.

Table C-1 Oracle Data Dictionary View Names and Teradata Equivalents

View Name Teradata System Table Name

ALL_CATALOG DBC.TablesX + DBC.IndicesX

ALL_COL_COMMENTS DBC.ColumnsX

ALL_CONS_COLUMNS DBC.Indices

ALL_CONSTRAINTS DBC.IndicesX

ALL_IND_COLUMNS DBC.Indices + DBC.Tables + DBC.Columns

ALL_INDEXES DBC.Indices

ALL_OBJECTS DBC.IndicesX + DBC.TablesX

ALL_TAB_COLUMNS DBC.ColumnsX + DBC.TablesX

ALL_TAB_COMMENTS DBC.Tables

ALL_TABLES DBC.TablesX

ALL_USERS DBC.Databases

ALL_VIEWS DBC.Tables

DBA_CATALOG DBC.Tables + DBC.Indices

DBA_COL_COMMENTS DBC.Columns + DBC.Tables

DBA_OBJECTS DBC.Indices + DBC.Tables

DBA_TAB_COLUMNS DBC.Columns + DBC.Tables

DBA_TAB_COMMENTS DBC.Tables

DBA_TABLES DBC.Tables

DICT_COLUMNS DBC.Columns

DICTIONARY DBC.Tables

DUAL DBC.Tables

USER_CATALOG DBC.Tables + DBC.Indices

USER_COL_COMMENTS DBC.Columns

USER_CONS_COLUMNS DBC.Indices

USER_CONSTRAINTS DBC.IndicesX

USER_IND_COLUMNS DBC.Indices + DBC.Tables + DBC.Columns

USER_INDEXES DBC.Indices

USER_OBJECTS DBC.Indices + DBC.Tables

USER_TAB_COLUMNS DBC.ColumnsX + DBC.TablesX

USER_TAB_COMMENTS DBC.TablesX

Appendix CData Dictionary Mapping

C-3

Table C-1 (Cont.) Oracle Data Dictionary View Names and Teradata Equivalents

View Name Teradata System Table Name

USER_TABLES DBC.Tables

USER_USERS DBC.DatabasesX

USER_VIEWS DBC.Tables

Default Column ValuesThere is a minor difference between the gateway data dictionary and a typical Oracledatabase data dictionary. The Oracle database columns that are missing in a Teradatasystem catalog table are filled with zeros, spaces, null values, not-applicable values(N.A.), or default values, depending on the column type.

Gateway Data Dictionary DescriptionsThe gateway data dictionary tables and views provide the following information:

• Name, data type, and width of each column

• The contents of columns with fixed values

They are described here with information retrieved by an SQL*PLUS DESCRIBEcommand. The values in the Null? column might differ from the Oracle database datadictionary tables and views. Any hardcoded default value is shown to the right of anitem, but this is not information returned by DESCRIBE.

ALL_CATALOGTable C-2 ALL_CATALOG

Name Type Value

OWNER VARCHAR2(30) -

TABLE_NAME VARCHAR2(30) -

TABLE_TYPE VARCHAR2(11) "TABLE", "VIEW", or"INDEX"

ALL_COL_COMMENTSTable C-3 ALL_COL_COMMENTS

Name Type Value



COLUMN_NAME VARCHAR2(30) -

Appendix CGateway Data Dictionary Descriptions

C-4

Table C-3 (Cont.) ALL_COL_COMMENTS

Name Type Value

COMMENTS VARCHAR2(4000) " "

ALL_CONS_COLUMNSTable C-4 ALL_CONS_COLUMNS

Name Type Value


CONSTRAINT_NAME VARCHAR2(30) -



POSITION NUMBER -

ALL_CONSTRAINTSTable C-5 ALL_CONSTRAINTS

Name Type Value



CONSTRAINT_TYPE VARCHAR2(1) "R" or "P"


SEARCH_CONDITION VARCHAR2(1) " "

R_OWNER VARCHAR2(30) " "

R_CONSTRAINT_NAME VARCHAR2(30) " "

DELETE_RULE VARCHAR2(9) " "

STATUS VARCHAR2(8) " "

DEFERRABLE VARCHAR2(14) " "

DEFERRED VARCHAR2(9) " "

VALIDATED VARCHAR2(13) " "

GENERATED VARCHAR2(14) " "

BAD VARCHAR2(3) " "

RELY VARCHAR2(4) " "

LAST_CHANGE DATE NULL

INDEX_OWNER VARCHAR2(30) " "

INDEX_NAME VARCHAR2(30) " "

Appendix CALL_CONS_COLUMNS

C-5

Table C-5 (Cont.) ALL_CONSTRAINTS

Name Type Value

INVALID VARCHAR2(7) " "

VIEW_RELATED VARCHAR2(14) " "

ALL_IND_COLUMNSTable C-6 ALL_IND_COLUMNS

Name Type Value

INDEX_OWNER VARCHAR2(30) -

INDEX_NAME VARCHAR2(30) -

TABLE_OWNER VARCHAR2(30) -



COLUMN_POSITION NUMBER -

COLUMN_LENGTH NUMBER -

DESCEND VARCHAR2(4) "DESC" or "ASC"

ALL_INDEXESTable C-7 ALL_INDEXES

Name Type Value



INDEX_TYPE VARCHAR2(27) " "



TABLE_TYPE VARCHAR2(5) "TABLE"

UNIQUENESS VARCHAR2(9) "UNIQUE" or"NONUNIQUE"

COMPRESSION VARCHAR2(8) " "

PREFIX_LENGTH NUMBER 0

TABLESPACE_NAME VARCHAR2(30) " "

INI_TRANS NUMBER 0

MAX_TRANS NUMBER(10) 0

INITIAL_EXTENT NUMBER(10) 0

Appendix CALL_IND_COLUMNS

C-6

Table C-7 (Cont.) ALL_INDEXES

Name Type Value

NEXT_EXTENT NUMBER(10) 0

MIN_EXTENTS NUMBER(10) 0

MAX_EXTENTS NUMBER(10) 0

PCT_INCREASE NUMBER(10) 0

PCT_THRESHOLD NUMBER(10) 0

INCLUDE_COLUMN NUMBER(10) 0

FREELISTS NUMBER(10) 0

FREELIST_GROUPS NUMBER(10) 0

PCT_FREE NUMBER(10) 0

LOGGING VARCHAR2(3) " "

BLEVEL NUMBER 0

LEAF_BLOCKS NUMBER 0

DISTINCT_KEYS NUMBER -

AVG_LEAF_BLOCKS_PER_KEY NUMBER 0

AVG_DATA_BLOCKS_PER_KEY NUMBER 0

CLUSTERING_FACTOR NUMBER 0

STATUS CHAR(1) " "

NUM_ROWS NUMBER 0

SAMPLE_SIZE NUMBER 0

LAST_ANALYZED DATE NULL

DEGREE VARCHAR2(40) " "

INSTANCES VARCHAR2(3) " "

PARTITIONED VARCHAR2(3) " "

TEMPORARY VARCHAR2(1) " "


SECONDARY VARCHAR2(1) " "

BUFFER_POOL VARCHAR2(7) " "

USER_STATS VARCHAR2(3) " "

DURATION VARCHAR2(15) " "

PCT_DIRECT_ACCESS NUMBER 0

ITYP_OWNER VARCHAR2(30) " "

ITYP_NAME VARCHAR2(30) " "

PARAMETERS VARCHAR2(1000) " "

GLOBAL_STATS VARCHAR2(3) " "

DOMIDX_STATUS VARCHAR2(12) " "

Appendix CALL_INDEXES

C-7

Table C-7 (Cont.) ALL_INDEXES

Name Type Value

DOMIDX_OPSTATUS VARCHAR2(6) " "

FUNCIDX_STATUS VARCHAR2(8) " "

JOIN_INDEX VARCHAR2(3)

IOT_REDUNDANT_PKEY_ELIM VARCHAR2(3)

DROPPED VARCHAR2(3)

VISIBILITY VARCHAR2(9)

DOMIDX_MANAGEMENT VARCHAR2(14)

ALL_OBJECTSTable C-8 ALL_OBJECTS

Name Type Value


OBJECT_NAME VARCHAR2(30) -

SUBOBJECT_NAME VARCHAR2(30) NULL

OBJECT_ID NUMBER 0

DATA_OBJECT_ID NUMBER 0

OBJECT_TYPE VARCHAR2(19) "TABLE" or "VIEW" or"INDEX" or"PROCEDURE"

CREATED DATE NULL

LAST_DDL_TIME DATE NULL

TIMESTAMP VARCHAR2(19) NULL

STATUS VARCHAR2(7) NULL

TEMPORARY VARCHAR2(1) NULL

GENERATED VARCHAR2(1) NULL

SECONDARY VARCHAR2(1) NULL

NAMESPACE NUMBER NULL

EDITION_NAME VARCHAR2(30) NULL

Appendix CALL_OBJECTS

C-8

ALL_TAB_COLUMNSTable C-9 ALL_TAB_COLUMNS

Name Type Value




DATA_TYPE VARCHAR2(106) -

DATA_TYPE_MOD VARCHAR2(3) " "

DATA_TYPE_OWNER VARCHAR2(30) " "

DATA_LENGTH NUMBER -

DATA_PRECISION NUMBER -

DATA_SCALE NUMBER -

NULLABLE VARCHAR2(1) "Y" or "N"

COLUMN_ID NUMBER -

DEFAULT_LENGTH NUMBER 0

DATA_DEFAULT VARCHAR2(1024) " "

NUM_DISTINCT NUMBER 0

LOW_VALUE RAW(32) 0

HIGH_VALUE RAW(32) 0

DENSITY NUMBER 0

NUM_NULLS NUMBER 0

NUM_BUCKETS NUMBER 0



CHARACTER_SET_NAME VARCHAR2(44) " "

CHAR_COL_DECL_LENGTH NUMBER 0



AVG_COL_LEN NUMBER 0

CHAR_LENGTH NUMBER

CHAR_USED VARCHAR2(1)

V80_FMT_IMAGE VARCHAR2(3)

DATA_UPGRADED VARCHAR2(3)

HISTOGRAM VARCHAR2(15)

Appendix CALL_TAB_COLUMNS

C-9

ALL_TAB_COMMENTSTable C-10 ALL_TAB_COMMENTS

Name Type Value



TABLE_TYPE VARCHAR2(11) "TABLE" or "VIEW"


ALL_TABLESTable C-11 ALL_TABLES

Name Type Value




CLUSTER_NAME VARCHAR2(30) " "

IOT_NAME VARCHAR2(8) " "

PCT_FREE NUMBER 0

PCT_USED NUMBER 0

INI_TRANS NUMBER 0

MAX_TRANS NUMBER 0

INITIAL_EXTENT NUMBER 0

NEXT_EXTENT NUMBER 0

MIN_EXTENTS NUMBER 0

MAX_EXTENTS NUMBER 0

PCT_INCREASE NUMBER 0

FREELISTS NUMBER 0

FREELIST_GROUPS NUMBER 0


BACKED_UP VARCHAR2(1) " "

NUM_ROWS NUMBER -

BLOCKS NUMBER -

EMPTY_BLOCKS NUMBER 0

AVG_SPACE NUMBER 0

CHAIN_CNT NUMBER 0

Appendix CALL_TAB_COMMENTS

C-10

Table C-11 (Cont.) ALL_TABLES

Name Type Value

AVG_ROW_LEN NUMBER 0

AVG_SPACE_FREELIST_BLOCKS NUMBER 0

NUM_FREELIST_BLOCKS NUMBER 0



CACHE VARCHAR2(5) " "

TABLE_LOCK VARCHAR2(8) " "




IOT_TYPE VARCHAR2(12) " "

TEMPORARY VARCHR2(1) " "

SECONDARY VARCHR2(1) " "

NESTED VARCHAR2(3) " "


ROW_MOVEMENT VARCHAR2(8) " "




SKIP_CORRUPT VARCHAR2(8) " "

MONITORING VARCHAR2(3) " "

CLUSTER_OWNER VARCHAR2(30)

DEPENDENCIES VARCHAR2(8)

COMPRESSION VARCHAR2(8)

DROPPED VARCHAR2(3)

ALL_USERSTable C-12 ALL_USERS

Name Type Value

USERNAME VARCHAR2(30) -

USER_ID NUMBER 0

CREATED DATE NULL

Appendix CALL_USERS

C-11

ALL_VIEWSTable C-13 ALL_VIEWS

Name Type Value


VIEW_NAME VARCHAR2(30) -

TEXT_LENGTH NUMBER 0

TEXT VARCHAR2(1) " "

TYPE_TEXT_LENGTH NUMBER 0

TYPE_TEXT VARCHAR2(4000) " "

OID_TEXT_LENGTH NUMBER 0

OID_TEXT VARCHAR2(4000) " "

VIEW_TYPE_OWNER VARCHAR2(30) " "

VIEW_TYPE VARCHAR2(30) " "

SUPERVIEW_NAME VARCHAR2(30)

EDITIONING_VIEW VARCHAR2(1)

READ_ONLY VARCHAR2(1)

DBA_CATALOGTable C-14 DBA_CATALOG

Name Type Value




DBA_COL_COMMENTSTable C-15 DBA_COL_COMMENTS

Name Type Value





Appendix CALL_VIEWS

C-12

DBA_OBJECTSTable C-16 DBA_OBJECTS

Name Type Value




OBJECT_ID NUMBER 0



CREATED DATE NULL







NAMESPACE NUMBER

EDITION_NAME VARCHAR2(30)

DBA_TAB_COLUMNSTable C-17 DBA_TAB_COLUMNS

Name Type Value









DATA_SCALE NUMBER -


COLUMN_ID NUMBER -

Appendix CDBA_OBJECTS

C-13

Table C-17 (Cont.) DBA_TAB_COLUMNS

Name Type Value


DATA_DEFAULT VARCHAR2(1024) " "


LOW_VALUE RAW(32) 0


DENSITY NUMBER 0

NUM_NULLS NUMBER 0









CHAR_LENGTH NUMBER





DBA_TAB_COMMENTSTable C-18 DBA_TAB_COMMENTS

Name Type Value





Appendix CDBA_TAB_COMMENTS

C-14

DBA_TABLESTable C-19 DBA_TABLES

Name Type Value






STATUS VARCHAR2(8)

PCT_FREE NUMBER 0

PCT_USED NUMBER 0

INI_TRANS NUMBER 0

MAX_TRANS NUMBER 0






FREELISTS NUMBER 0




NUM_ROWS NUMBER -

BLOCKS NUMBER -


AVG_SPACE NUMBER 0

CHAIN_CNT NUMBER 0










Appendix CDBA_TABLES

C-15

Table C-19 (Cont.) DBA_TABLES

Name Type Value













CLUSTER_OWNER VARCHAR2(30)

DEPENDENCIES VARCHAR2(8)

COMPRESSION VARCHAR2(8)

DROPPED VARCHAR2(3)

DICT_COLUMNSTable C-20 DICT_COLUMNS

Name Type Value




DICTIONARYTable C-21 DICTIONARY

Name Type Value



Appendix CDICT_COLUMNS

C-16

DUALTable C-22 DUAL

Name Type Value

DUMMY VARCHAR2(1) "X"

USER_CATALOGTable C-23 USER_CATALOG

Name Type Value



USER_COL_COMMENTSTable C-24 USER_COL_COMMENTS

Name Type Value




USER_CONS_COLUMNSTable C-25 USER_CONS_COLUMNS

Name Type Value





POSITION NUMBER -

Appendix CDUAL

C-17

USER_CONSTRAINTSTable C-26 USER_CONSTRAINTS

Name Type Value



CONSTRAINT_TYPE VARCHAR2(1) "R" or "P"


SEARCH_CONDITION CHAR(1) " "

R_OWNER VARCHAR2(30) -

R_CONSTRAINT_NAME VARCHAR2(30) -

DELETE_RULE VARCHAR2(9) " "


DEFERRABLE VARCHAR2(14) " "

DEFERRED VARCHAR2(9) " "

VALIDATED VARCHAR2(13) " "


BAD VARCHAR2(3) " "

RELY VARCHAR2(4) " "

LAST_CHANGE DATE NULL

INDEX_OWNER VARCHAR2(30)

INDEX_NAME VARCHAR2(30)

INVALID VARCHAR2(7)

VIEW_RELATED VARCHAR2(14)

USER_IND_COLUMNSTable C-27 USER_IND_COLUMNS

Name Type Value




COLUMN_POSITION NUMBER -

COLUMN_LENGTH NUMBER -

CHAR_LENGTH NUMBER

DESCEND VARCHAR2(4) "DESC" or "ASC"

Appendix CUSER_CONSTRAINTS

C-18

USER_INDEXESTable C-28 USER_INDEXES

Name Type Value


INDEX_TYPE VARCHAR2(27) " "



TABLE_TYPE VARCHAR2(11) "TABLE"

UNIQUENESS VARCHAR2(9) "UNIQUE" or"NONUNIQUE"

COMPRESSION VARCHAR2(8) " "

PREFIX_LENGTH NUMBER 0


INI_TRANS NUMBER 0

MAX_TRANS NUMBER 0






PCT_THRESHOLD NUMBER 0

INCLUDE_COLUMN NUMBER 0

FREELISTS NUMBER 0


PCT_FREE NUMBER 0


BLEVEL NUMBER 0

LEAF_BLOCKS NUMBER 0

DISTINCT_KEYS NUMBER -

AVG_LEAF_BLOCKS_PER_KEY NUMBER 0

AVG_DATA_BLOCKS_PER_KEY NUMBER 0

CLUSTERING_FACTOR NUMBER 0


NUM_ROWS NUMBER 0



Appendix CUSER_INDEXES

C-19

Table C-28 (Cont.) USER_INDEXES

Name Type Value










PCT_DIRECT_ACCESS NUMBER 0

ITYP_OWNER VARCHAR2(30) " "

ITYP_NAME VARCHAR2(30) " "

PARAMETERS VARCHAR2(1000) " "


DOMIDX_STATUS VARCHAR2(12) " "

DOMIDX_OPSTATUS VARCHAR2(6) " "

FUNCIDX_STATUS VARCHAR2(8) " "

JOIN_INDEX VARCHAR2(3)

IOT_REDUNDANT_PKEY_ELIM VARCHAR2(3)

DROPPED VARCHAR2(3)

VISIBILITY VARCHAR2(10)

DOMIDX_MANAGEMENT VARCHAR2(14)

USER_OBJECTSTable C-29 USER_OBJECTS

Name Type Value



OBJECT_ID NUMBER 0



CREATED DATE NULL

Appendix CUSER_OBJECTS

C-20

Table C-29 (Cont.) USER_OBJECTS

Name Type Value







NAMESPACE NUMBER

EDITION_NAME VARCHAR2(30)

USER_TAB_COLUMNSTable C-30 USER_TAB_COLUMNS

Name Type Value








DATA_SCALE NUMBER -


COLUMN_ID NUMBER -


DATA_DEFAULT CHAR(1) " "


LOW_VALUE RAW(32) 0


DENSITY NUMBER 0

NUM_NULLS NUMBER 0





Appendix CUSER_TAB_COLUMNS

C-21

Table C-30 (Cont.) USER_TAB_COLUMNS

Name Type Value





CHAR_LENGTH NUMBER





USER_TAB_COMMENTSTable C-31 USER_TAB_COMMENTS

Name Type Value




USER_TABLESTable C-32 USER_TABLES

Name Type Value





STATUS VARCHAR2(8)

PCT_FREE NUMBER 0

PCT_USED NUMBER 0

INI_TRANS NUMBER 0

MAX_TRANS NUMBER 0




Appendix CUSER_TAB_COMMENTS

C-22

Table C-32 (Cont.) USER_TABLES

Name Type Value



FREELISTS NUMBER 0




NUM_ROWS NUMBER -

BLOCKS NUMBER -


AVG_SPACE NUMBER 0

CHAIN_CNT NUMBER 0






















Appendix CUSER_TABLES

C-23

USER_USERSTable C-33 USER_USERS

Name Type Value

USERNAME VARCHAR2(30) -

USER_ID NUMBER 0

ACCOUNT_STATUS VARCHAR2(32) "OPEN"

LOCK_DATE DATE NULL

EXPIRY_DATE DATE NULL

DEFAULT_TABLESPACE VARCHAR2(30) NULL

TEMPORARY_TABLESPACE VARCHAR2(30) NULL

CREATED DATE NULL

INITIAL_RSRC_CONSUMER_GROUP VARCHAR2(30) NULL

EXTERNAL_NAME VARCHAR2(4000) NULL

USER_VIEWSTable C-34 USER_VIEWS

Name Type Value

VIEW_NAME VARCHAR2(30) -

TEXT_LENGTH NUMBER 0

TEXT CHAR(1) " "

TYPE_TEXT_LENGTH NUMBER 0

TYPE_TEXT VARCHAR2(4000) " "

OID_TEXT_LENGTH NUMBER 0

OID_TEXT VARCHAR2(4000) " "

VIEW_TYPE_OWNER VARCHAR2(30) " "

VIEW_TYPE VARCHAR2(30) " "

SUPERVIEW_NAME VARCHAR2(30)

EDITIONING_VIEW VARCHAR2(1)

Appendix CUSER_USERS

C-24

DInitialization Parameters

The Oracle database initialization parameters in the init.ora file are distinct fromgateway initialization parameters. Set the gateway parameters in the initializationparameter file using an agent-specific mechanism, or set them in the Oracle datadictionary using the DBMS_HS package. The gateway initialization parameter file mustbe available when the gateway is started.

The following topics contain a list of the gateway initialization parameters that can beset for each gateway and their description. The topics also describe the initializationparameter file syntax:

• Initialization Parameter File Syntax

• Oracle Database Gateway for Teradata Initialization Parameters

Initialization Parameter File SyntaxThe syntax for the initialization parameter file is as follows:

• The file is a sequence of commands.

• Each command should start on a separate line.

• End of line is considered a command terminator (unless escaped with abackslash).

• If there is a syntax error in an initialization parameter file, none of the settings takeeffect.

• Set the parameter values as follows:

[SET][PRIVATE] parameter=value

Where:

parameter is an initialization parameter name. It is a string of characters startingwith a letter and consisting of letters, digits and underscores. Initializationparameter names are case sensitive.

value is the initialization parameter value. It is case sensitive. An initializationparameter value is either:

– A string of characters that does not contain any backslashes, white space ordouble quotation marks (")

– A quoted string beginning with a double quotation mark and ending with adouble quotation mark. The following can be used inside a quoted string:

* backslash (\) is the escape character

* \n inserts a new line

* \t inserts a tab

* \" inserts a double quotation mark

D-1

* \\ inserts a backslash

A backslash at the end of the line continues the string on the next line. If abackslash precedes any other character then the backslash is ignored.

For example, to enable tracing for an agent, set the HS_FDS_TRACE_LEVELinitialization parameter as follows:

HS_FDS_TRACE_LEVEL=ON

SET and PRIVATE are optional keywords. You cannot use either as an initializationparameter name. Most parameters are needed only as initialization parameters, soyou usually do not need to use the SET or PRIVATE keywords. If you do not specifyeither SET or PRIVATE, the parameter is used only as an initialization parameter forthe agent.

SET specifies that, in addition to being used as an initialization parameter, theparameter value is set as an environment variable for the agent process. Use SETfor parameter values that the drivers or non-Oracle system need as environmentvariables.

PRIVATE specifies that the initialization parameter should be private to the agentand should not be uploaded to the Oracle database. Most initialization parametersshould not be private. If, however, you are storing sensitive information like apassword in the initialization parameter file, then you may not want it uploaded tothe server because the initialization parameters and values are not encryptedwhen uploaded. Making the initialization parameters private prevents the uploadfrom happening and they do not appear in dynamic performance views. UsePRIVATE for the initialization parameters only if the parameter value includessensitive information such as a user name or password.

SET PRIVATE specifies that the parameter value is set as an environment variablefor the agent process and is also private (not transferred to the Oracle database,not appearing in dynamic performance views or graphical user interfaces).

Oracle Database Gateway for Teradata InitializationParameters

The initialization file parameters that can be set for the Oracle Database Gateway forTeradata are as follows:

• HS_DB_DOMAIN

• HS_DB_INTERNAL_NAME

• HS_DB_NAME

• HS_DESCRIBE_CACHE_HWM

• HS_LANGUAGE

• HS_LONG_PIECE_TRANSFER_SIZE

• HS_FDS_TRANSACTION_ISOLATION

• HS_OPEN_CURSORS

• HS_RPC_FETCH_REBLOCKING

• HS_RPC_FETCH_SIZE

Appendix DOracle Database Gateway for Teradata Initialization Parameters

D-2

• HS_TIME_ZONE

• HS_TRANSACTION_MODEL

• IFILE

• HS_FDS_TIMESTAMP_MAPPING

• HS_FDS_DATE_MAPPING

• HS_FDS_CONNECT_INFO

• HS_FDS_DEFAULT_OWNER

• HS_FDS_PROC_IS_FUNC

• HS_FDS_RECOVERY_ACCOUNT

• HS_FDS_RECOVERY_PWD

• HS_FDS_TRACE_LEVEL

• HS_FDS_TRANSACTION_LOG

• HS_FDS_FETCH_ROWS

• HS_IDLE_TIMEOUT

• HS_NLS_LENGTH_SEMANTICS

• HS_KEEP_REMOTE_COLUMN_SIZE

• HS_FDS_REMOTE_DB_CHARSET

• HS_FDS_SUPPORT_STATISTICS

• HS_FDS_ARRAY_EXEC

HS_DB_DOMAIN

Property Description

Default value WORLD

Range of values 1 to 199 characters

Specifies a unique network sub-address for a non-Oracle system. The HS_DB_DOMAINinitialization parameter is similar to the DB_DOMAIN initialization parameter, described inthe Oracle Database Reference. The HS_DB_DOMAIN initialization parameter is requiredif you use the Oracle Names server. The HS_DB_NAME and HS_DB_DOMAIN initializationparameters define the global name of the non-Oracle system.

Note:

The HS_DB_NAME and HS_DB_DOMAIN initialization parameters must combine toform a unique address in a cooperative server environment.

Appendix DHS_DB_DOMAIN

D-3

HS_DB_INTERNAL_NAME


Default value 01010101

Range of values 1 to 16 hexadecimal characters

Specifies a unique hexadecimal number identifying the instance to which theHeterogeneous Services agent is connected. This parameter's value is used as part ofa transaction ID when global name services are activated. Specifying a nonuniquenumber can cause problems when two-phase commit recovery actions are necessaryfor a transaction.

HS_DB_NAME


Default value HO

Range of values 1 to 8 characters

Specifies a unique alphanumeric name for the data store given to the non-Oraclesystem. This name identifies the non-Oracle system within the cooperative serverenvironment. The HS_DB_NAME and HS_DB_DOMAIN initialization parameters define theglobal name of the non-Oracle system.

HS_DESCRIBE_CACHE_HWM


Default value 100

Range of values 1 to 4000

Specifies the maximum number of entries in the describe cache used byHeterogeneous Services. This limit is known as the describe cache high water mark.The cache contains descriptions of the mapped tables that Heterogeneous Servicesreuses so that it does not have to re-access the non-Oracle data store.

If you are accessing many mapped tables, increase the high water mark to improveperformance. Increasing the high water mark improves performance at the cost ofmemory usage.

HS_LANGUAGE


Default value System-specific

Range of values Any valid language name (up to 255 characters)

Appendix DHS_DB_INTERNAL_NAME

D-4

Provides Heterogeneous Services with character set, language, and territoryinformation of the non-Oracle data source. The value must use the following format:

language[_territory.character_set]

Note:

The globalization support initialization parameters affect error messages, thedata for the SQL Service, and parameters in distributed external procedures.

Character SetsIdeally, the character sets of the Oracle database and the non-Oracle data source arethe same. In almost all cases, HS_LANGUAGE should be set exactly the same as Oracledatabase character set for optimal character set mapping and performance. If they arenot the same, Heterogeneous Services attempts to translate the character set of thenon-Oracle data source to the Oracle database character set, and back again. Thetranslation can degrade performance. In some cases, Heterogeneous Services cannottranslate a character from one character set to another.

Note:

The specified character set must be a superset of the operating systemcharacter set on the platform where the agent is installed.

As more Oracle databases and non-Oracle databases use Unicode as databasecharacter sets, it is preferable to also run the gateway in Unicode character set. To doso, you must set HS_LANGUAGE=AL32UTF8. However, when the gateway runs onWindows, the Microsoft ODBC Driver Manager interface can exchange data only in thedouble-byte character set, UCS2. This results in extra ratio expansion of describedbuffer and column sizes. Refer to HS_FDS_REMOTE_DB_CHARSET for instructionon how to adjust to correct sizes.

LanguageThe language component of the HS_LANGUAGE initialization parameter determines:

• Day and month names of dates

• AD, BC, PM, and AM symbols for date and time

• Default sorting mechanism

Note that Oracle does not determine the language for error messages for the genericHeterogeneous Services messages (ORA-25000 through ORA-28000). These arecontrolled by the session settings in the Oracle database.

TerritoryThe territory clause specifies the conventions for day and week numbering, defaultdate format, decimal character and group separator, and ISO and local currency

Appendix DHS_LANGUAGE

D-5

symbols. Note that the level of globalization support between the Oracle database andthe non-Oracle data source depends on how the gateway is implemented.

HS_LONG_PIECE_TRANSFER_SIZE


Default value 64 KB

Range of values Any value up to 2 GB

Sets the size of the piece of LONG data being transferred. A smaller piece size meansless memory requirement, but more round-trips to fetch all the data. A larger piece sizemeans fewer round-trips, but more of a memory requirement to store the intermediatepieces internally. Thus, the initialization parameter can be used to tune a system forthe best performance, with the best trade-off between round-trips and memoryrequirements, and network latency or response time.

HS_OPEN_CURSORS


Default value 50

Range of values 1 to the value of Oracle's OPEN_CURSORS initialization parameter

Defines the maximum number of cursors that can be open on one connection to anon-Oracle system instance.

The value never exceeds the number of open cursors in the Oracle database.Therefore, setting the same value as the OPEN_CURSORS initialization parameter in theOracle database is recommended.

HS_RPC_FETCH_REBLOCKING


Default value ON

Range of values OFF or ON

Controls whether Heterogeneous Services attempts to optimize performance of datatransfer between the Oracle database and the Heterogeneous Services agentconnected to the non-Oracle data store.

The following values are possible:

• OFF disables reblocking of fetched data so that data is immediately sent from agentto server.

• ON enables reblocking, which means that data fetched from the non-Oracle systemis buffered in the agent and is not sent to the Oracle database until the amount offetched data is equal or higher than the value of HS_RPC_FETCH_SIZE initialization

Appendix DHS_LONG_PIECE_TRANSFER_SIZE

D-6

parameter. However, any buffered data is returned immediately when a fetchindicates that no more data exists or when the non-Oracle system reports an error.

HS_RPC_FETCH_SIZE


Default value 50000

Range of values 1 to 10000000

Tunes internal data buffering to optimize the data transfer rate between the server andthe agent process.

Increasing the value can reduce the number of network round-trips needed to transfera given amount of data, but also tends to increase data bandwidth and to reducelatency as measured between issuing a query and completion of all fetches for thequery. Nevertheless, increasing the fetch size can increase latency for the initial fetchresults of a query, because the first fetch results are not transmitted until additionaldata is available.

HS_TIME_ZONE


Default value for'[+|-]hh:mm'

Derived from the NLS_TERRITORY initialization parameter

Range of values for'[+|-]hh:mm'

Any valid datetime format mask

Specifies the default local time zone displacement for the current SQL session. Theformat mask, [+|-]hh:mm, is specified to indicate the hours and minutes before or afterUTC (Coordinated Universal Time—formerly Greenwich Mean Time). For example:

HS_TIME_ZONE = [+ | -] hh:mm

HS_TRANSACTION_MODEL


Default Value COMMIT_CONFIRM

Range of Values COMMIT_CONFIRM, READ_ONLY, SINGLE_SITE,READ_ONLY_AUTOCOMMIT, SINGLE_SITE_AUTOCOMMIT

Specifies the type of transaction model that is used when the non-Oracle database isupdated by a transaction.

The following values are possible:

• COMMIT_CONFIRM provides read and write access to the non-Oracle database andallows the gateway to be part of a distributed update. To use the commit-confirmmodel, the following items must be created in the non-Oracle database:

Appendix DHS_RPC_FETCH_SIZE

D-7

– Transaction log table. The default table name is HS_TRANSACTION_LOG. Adifferent name can be set using the HS_FDS_TRANSACTION_LOG parameter. Thetransaction log table must be granted SELECT, DELETE, and INSERT privilegesset to public.

– Recovery account. The account name is assigned with theHS_FDS_RECOVERY_ACCOUNT parameter.

– Recovery account password. The password is assigned with theHS_FDS_RECOVERY_PWD parameter.

• READ_ONLY provides read access to the non-Oracle database.

• SINGLE_SITE provides read and write access to the non-Oracle database.However, the gateway cannot participate in distributed updates.

• READ_ONLY_AUTOCOMMIT provides read only access to the non-Oracle database thatdoes not use logging.

• SINGLE_SITE_AUTOCOMMIT provides read and write access to the non-Oracledatabase without logging. The gateway cannot participate in distributed updates.Moreover, any update to the non-Oracle database is committed immediately.

IFILE


Default value None

Range of values Valid parameter file names

Use the IFILE initialization parameter to embed another initialization file within thecurrent initialization file. The value should be an absolute path and should not containenvironment variables. The three levels of nesting limit do not apply.

See Also:

Oracle Database Reference

HS_FDS_TIMESTAMP_MAPPING


Default Value DATE

Range of Values CHAR|DATE|TIMESTAMP

Syntax HS_FDS_TIMESTAMP_MAPPING={CHAR|DATE|TIMESTAMP}

If set to CHAR , then non-Oracle target timestamp would be mapped to CHAR(26). If setto DATE (default), then non-Oracle target timestamp would be mapped to Oracle DATE.If set to TIMESTAMP, then non-Oracle target timestamp would be mapped to OracleTIMESTAMP.

Appendix DIFILE

D-8

HS_FDS_DATE_MAPPING


Default Value DATE

Range of Values DATE|CHAR

Syntax HS_FDS_DATE_MAPPING={DATE|CHAR}

If set to CHAR, then non-oracle target date would be mapped to CHAR(10). If set to DATE,then non-Oracle target date would be mapped to Oracle date.

HS_FDS_CONNECT_INFO


Default Value None

Range of Values Not applicable

HS_FDS_CONNECT_INFO that describes the connection to the non-Oracle system.

The default initialization parameter file already has an entry for this parameter. Thesyntax for HS_FDS_CONNECT_INFO for the gateway is as follows:

HS_FDS_CONNECT_INFO=host_alias:port_number[/database_name]

where, host_alias is the host alias name or IP address of the machine hosting theTeradata database, port_number is the port number of the Teradata database server,and database_name is the Teradata database name. The database_name variable isoptional.

This release supports IPv6 format, so you can enter IPv6 format in place of hostname,but you need to wrap square brackets around the IPv6 specification.

For example,

HS_FDS_CONNECT_INFO=[2001:0db8:20c:f1ff:fec6:38af]:port_number/…

HS_FDS_DEFAULT_OWNER


Default Value None

Range of Values Not applicable

The name of the table owner that is used for the non-Oracle database tables if anowner is not specified in the SQL statements.

Appendix DHS_FDS_DATE_MAPPING

D-9

Note:

If this parameter is not specified and the owner is not explicitly specified inthe SQL statement, then the user name of the Oracle user or the user namespecified when creating the database link is used.

HS_FDS_TRANSACTION_ISOLATION


Default Value SERIALIZABLE

Range of Values {READ_UNCOMMITTED READ_COMMITTED REPEATABLE_READSERIALIZABLE}

Syntax HS_FDS_ISOLATION_LEVEL={{READ_UNCOMMITTED|READ_COMMITTED|REPEATABLE_READ|SERIALIZABLE}

HS_FDS_TRANSACTION_ISOLATION specifies the isolation level that is used for thetransaction that the gateway opens on the non-Oracle database.

The isolation levels of READ_UNCOMMITTED, READ_COMMITTED, REPEATABLE_READ, andSERIALIZABLE are the four isolation levels defined in the SQL standard and adopted byboth ANSI and ISO/IEC. For additional information regarding them, see OracleDatabase Concepts.

Use caution when specifying an isolation level lower than the Oracle transactionisolation level being used, as the gateway transaction will have different PreventableRead Phenomena from what will occur in the Oracle database transaction.

HS_FDS_PROC_IS_FUNC


Default Value FALSE

Range of Values TRUE, FALSE

Enables return values from functions. By default, all stored procedures and functionsdo not return a return value to the user.

Note:

If you set this initialization parameter, you must change the syntax of theprocedure execute statement for all existing stored procedures to handlereturn values.

Appendix DHS_FDS_TRANSACTION_ISOLATION

D-10

HS_FDS_RECOVERY_ACCOUNT


Default Value RECOVER

Range of values Any valid user ID

Specifies the name of the recovery account used for the commit-confirm transactionmodel. An account with user name and password must be set up at the non-Oraclesystem. For more information about the commit-confirm model, see theHS_TRANSACTION_MODEL parameter.

The name of the recovery account is case sensitive.

HS_FDS_RECOVERY_PWD


Default Value RECOVER

Range of values Any valid password

Specifies the password of the recovery account used for the commit-confirmtransaction model set up at the non-Oracle system. For more information about thecommit-confirm model, see the HS_TRANSACTION_MODEL parameter.

The name of the password of the recovery account is case sensitive.

HS_FDS_TRACE_LEVEL


Default Value OFF

Range of values OFF, ON, DEBUG

Specifies whether error tracing is turned on or off for gateway connectivity.

The following values are valid:

• OFF disables the tracing of error messages.

• ON enables the tracing of error messages that occur when you encounterproblems. The results are written by default to a gateway log file in LOG directorywhere the gateway is installed.

• DEBUG enables the tracing of detailed error messages that can be used fordebugging.

Appendix DHS_FDS_RECOVERY_ACCOUNT

D-11

HS_FDS_TRANSACTION_LOG


Default Value HS_TRANSACTION_LOG

Range of Values Any valid table name

Specifies the name of the table created in the non-Oracle system for loggingtransactions. For more information about the transaction model, see theHS_TRANSACTION_MODEL parameter.

HS_FDS_FETCH_ROWS


Default Value 100

Range of Values Any integer between 1 and 1000

Syntax HS_FDS_FETCH_ROWS=num

HS_FDS_FETCH_ROWS specifies the fetch array size. This is the number of rows to befetched from the non-Oracle database and to return to Oracle database at one time.This parameter will be affected by the HS_RPC_FETCH_SIZE andHS_RPC_FETCH_REBLOCKING parameters.

HS_IDLE_TIMEOUT


Default Value 0 (no timeout)

Range of Values 0-9999 (minutes)

Syntax HS_IDLE_TIMEOUT=num

This feature is only available for Oracle Net TCP protocol. When there is no activity fora connected gateway session for this specified time period, the gateway session wouldbe terminated automatically with pending update (if any) rolled back.

HS_NLS_LENGTH_SEMANTICS


Default Value BYTE

Range of Values BYTE | CHAR

Syntax HS_NLS_LENGTH_SEMANTICS = { BYTE | CHAR }

This release of gateway has Character Semantics functionality equivalent to theOracle Database Character Semantics, that is, NLS_LENGTH_SEMANTICS. When

Appendix DHS_FDS_TRANSACTION_LOG

D-12

HS_NLS_LENGTH_SEMANTICS is set to CHAR, the (VAR)CHAR columns of Teradata are tobe interpreted as having CHAR semantics. The only situation the gateway does nothonor the HS_NLS_LENGTH_SEMANTICS=CHAR setting is when both Oracle database andthe gateway are on the same multi-byte character set

HS_KEEP_REMOTE_COLUMN_SIZE


Default Value OFF

Range of Values OFF | LOCAL | REMOTE |ALL

Syntax HS_KEEP_REMOTE_COLUMN_SIZE = OFF | LOCAL |REMOTE | ALL

Parameter type String

HS_KEEP_REMOTE_COLUMN_SIZE specifies whether to suppress ratio expansion whencomputing the length of (VAR)CHAR datatypes during data conversion from non-Oracledatabase to the gateway, and then to the Oracle database. When it is set to REMOTE,the expansion is suppressed between the non-Oracle database and the gateway.When it is set to LOCAL, the expansion is suppressed between the gateway and theOracle database. When it is set to ALL, the expansion is suppressed from the non-Oracle database to the Oracle database.

When the parameter is set, the expansion is suppressed when reporting the remotecolumn size, calculating the implicit resulting buffer size, and instantiating in the localOracle database. This has effect only for remote column size from non-Oracledatabase to the Oracle database. If the gateway runs on Windows andHS_LANGUAGE=AL32UTF8, then you must not specify this parameter, as it wouldinfluence other ratio related parameter operation. It has no effect for calculating ratiofor data moving from Oracle database to non-Oracle database through gateway duringINSERT, UPDATE, or DELETE.

HS_FDS_REMOTE_DB_CHARSET


Default Value None

Range of values Not applicable

Syntax HS_FDS_REMOTE_DB_CHARSET

This parameter is valid only when HS_LANGUAGE is set to AL32UTF8 and the gatewayruns on Windows. As more Oracle databases and non-Oracle databases use Unicodeas database character sets, it is preferable to also run the gateway in Unicodecharacter set. To do so, you must set HS_LANGUAGE=AL32UTF8. However, when thegateway runs on Windows, the Microsoft ODBC Driver Manager interface canexchange data only in the double-byte character set, UCS2. This results in extra ratioexpansion of described buffer and column sizes. To compensate, the gateway can re-adjust the column size if HS_FDS_REMOTE_DB_CHARSET is set to the corresponding non-Oracle database character set. For example,HS_FDS_REMOTE_DB_CHARSET=KO16KSC5601.

Appendix DHS_KEEP_REMOTE_COLUMN_SIZE

D-13

HS_FDS_SUPPORT_STATISTICS


Default Value TRUE

Range of values {TRUE|FALSE}

Syntax HS_FDS_SUPPORT_STATISTICS= {TRUE|FALSE}

We gather statistics from the non-Oracle database by default. You can choose todisable the gathering of remote database statistics by setting theHS_FDS_SUPPORT_STATISTICS parameter to FALSE.

HS_FDS_ARRAY_EXEC


Default Value TRUE

Range of values {TRUE|FALSE}

Syntax HS_FDS_ARRAY_EXEC= {TRUE|FALSE}

If set to TRUE, the gateway will use array operations for insert, update, deletestatements containing binds against the remote data source. The array size isdetermined by the value of the HS_FDS_FETCH_ROWS init parameter.

If set to FALSE, the gateway will not use array operations for insert, update, and deletestatements. Instead, a single statement will be issued for every value.

Appendix DHS_FDS_SUPPORT_STATISTICS

D-14

Index

AALTER statement, B-1Arithmetic operators, B-3

BBYTE data type, A-1BYTEINT data type, A-1

CCase rules, 2-9Case studies, 3-1CHAR data type, A-1character sets

Heterogeneous Services, D-5COMMIT

restrictions, 2-12Commit point site, 2-12Comparison operators, B-3CONNECT BY clause, 2-13COPY command, 2-13CREATE statement, B-1Cursor loops

restrictions, 2-12

DData definition language, B-1Data dictionary

views, C-2Data type

BYTE, A-1BYTEINT, A-1CHAR, A-1conversion, 2-10DATE, A-1DECIMAL, A-1FLOAT, A-1INTEGER, A-1LONG, A-1LONG VARCHAR, A-1RAW, A-1

Data type (continued)SMALLINT, A-1TIME, A-1TIMESTAMP, A-1VARBYTE, A-1VARCHAR, A-1VARCHAR2, A-1

DATE data type, A-1DDL statement, 2-12DECIMAL data type, A-1DELETE statement, 3-5, B-1, B-2demonstration build SQL script, 3-2Demonstration files, 3-2Demonstration tables, 3-2Demonstration tables build SQL script, 3-2describe cache high water mark

definition, D-4DROP statement, B-1

EError messages

error tracing, D-11Errors

ORA-02070, 2-12

Ffetch array size, with HS_FDS_FETCH_ROWS,

D-12FLOAT data type, A-1

GGateway

case studies, 3-1pass-through feature, 2-2supported functions, B-1supported SQL syntax, B-1

globalization supportHeterogeneous Services, D-4

GRANT statement, B-1Group functions, B-3

Index-1

HHeterogeneous Services

defining maximum number of open cursors,D-6

optimizing data transfer, D-6setting global name, D-4specifying cache high water mark, D-4tuning internal data buffering, D-7tuning LONG data transfer, D-6

Hexadecimal notation, 2-10HS_DB_NAME initialization parameter, D-4HS_DESCRIBE_CACHE_HWM initialization

parameter, D-4HS_FDS_CONNECT_INFO, D-9HS_FDS_DEFAULT_OWNER initialization

parameter, D-9HS_FDS_FETCH_ROWS parameter, D-12HS_FDS_PROC_IS_FUNC initialization

parameter, D-10HS_FDS_TRACE_LEVEL initialization

parameter, D-11enabling agent tracing, D-2

HS_FDS_TRANSACTION_ISOLATIONparameter, D-10

HS_FDS_TRANSACTION_LOG initializationparameter, D-12

HS_IDLE_TIMEOUT, D-12HS_KEEP_REMOTE_COLUMN_SIZE, D-13HS_LANGUAGE initialization parameter, D-4HS_LONG_PIECE_TRANSFER_SIZE

initialization parameter, D-6HS_NLS_LENGTH_SEMANTICS, D-12HS_OPEN_CURSORS initialization parameter,

D-6HS_RPC_FETCH_REBLOCKING initialization

parameter, D-6HS_RPC_FETCH_SIZE initialization parameter,

D-7HS_TIME_ZONE initialization parameter, D-7

IIFILE initialization parameter, D-8Initialization parameter file

customizing, D-1INSERT statement, 3-5, B-1, B-2INTEGER data type, A-1isolation level,

HS_FDS_TRANSACTION_ISOLATION,D-10

KKnown restrictions, 2-11

LLocking, database, 2-11LONG data type, A-1LONG VARCHAR data type, A-1

NNVL function, 3-4

OObjects, naming rules, 2-8ORA-02070, 2-12

Pparameters

gateway initialization fileHS_FDS_FETCH_ROWS, D-12HS_FDS_TRANSACTION_ISOLATION,

D-10Pass-Through Feature, 3-5Passing commands to database, 2-12PL/SQL, 2-14, 2-15

RRAW data type, A-1remote

DRDA database,HS_FDS_TRANSACTION_ISOLATION,D-10

ROLLBACKrestrictions, 2-12

ROWID, 2-13

Ssavepoint support, 2-12SELECT statement, 3-6, B-2, C-1SMALLINT data type, A-1SQL

statements,HS_FDS_TRANSACTION_ISOLATION,D-10

String functions, B-3SUM function, 3-4

TTIME data type, A-1TIMESTAMP data type, A-1transactional capability, 2-12

Index

Index-2

transactional integrity, 2-11TRUNCATE statement, B-1Two-phase commit, 2-12

UUPDATE statement, 3-5, B-2

VVARBYTE data type, A-1

VARCHAR data type, A-1VARCHAR2 data type, A-1

WWHERE CURRENT OF clause, 2-13

Index

3