Marketing Analytics - Stephan SorgerLogical Using logical commands (AND, OR) in commands Creating...

Marketing Analytics: Database Query with MySQL

Disclaimer:

• All logos, photos, etc. used in this presentation are the property of their respective

copyright owners and are used here for educational purposes only

© Stephan Sorger 2015. www.StephanSorger.com; Database Query with MySQL; SQL.1

http://www.stephansorger.com/

Category Description

Introduction Overview of database query languages

RDBMS Example of Relational Database Management System

Hosting Obtaining hosting server for MySQL (free or paid)

Setup Setting up the MySQL Server on hosting platforms

Import Importing databases into MySQL Server

Structure Data structure; Showing tables within databases

SHOW Commands to display data

SELECT Commands to choose certain pieces of data

Sorting Commands to sort data

Filtering Commands to filter data

Logical Using logical commands (AND, OR) in commands

Creating Creating, Dropping, and Altering databases and tables

Outline



Category Description

SQL Structured Query Language

Programming language for accessing RDBMS

RDBMS Relational Database Management System

SQL Consists of two items:

Data Definition Language: Syntax for defining data structures

Data Manipulation Language: Syntax for selecting, inserting

deleting, and updating data in databases

Top 3 Top 3 Database engines:

Oracle

MySQL

Microsoft SQL Server

MySQL Open source; Free; Available for Mac and PC

Manual: See dev.mysql.com/doc/index.html

Database Query: Introduction



RDBMS Database Example

Row: Record

Primary Key: Column with 100% unique entries

similar to Social Security Number

(‘Engine’ column will not work; duplicate entries)



MySQL: Hosting

Go to

000webhost.com

(or other similar

Web hosting service)

and get an account



MySQL Server:

Setup

Creating MySQL

Databases for

hosting accounts

on GoDaddy.com



For GoDaddy,

launch hosting

account to see

cPanel (shown).

Click on MySQL

Database Wizard

MySQL:

Server Setup



MySQL Server: Setup

Enter name for

database



MySQL Server: Setup

Enter username

and password



MySQL Server: Setup

Select privileges

for user



MySQL Server: Setup

Select

phpMyAdmin



MySQL: Importing Databases

Select your Database

(Database1)




Select Import




MySQL Sample

Databases:

dev.mysql.com/doc/index-other.html




Choose File:

Dataset:

world.sql

Click “Go”

(bottom of page)




Imported OK;

Click “Database1”



MySQL: Data Structure

Check “City” Table

within World database

Click on SQL tab




In SQL tab, enter

“SHOW DATABASES”

and hit “Go”

SQL commands

also called “queries”

are in ALL CAPS

Table entries are in lower case or Mixed Case




Shows databases:

information_schema

(already in SQL server)

Database1

(we created)




In SQL tab, enter

“SHOW TABLES”

and hit “Go”




Tables:

City

Country

Country Language



MySQL: SHOW Commands

View columns of table

Click on SQL tab

Syntax:

SHOW COLUMNS FROM (table)

Here:

SHOW COLUMNS FROM City

Then click Go




Results:

See columns from table

Note PRI (primary) key

Here, PRI = ID field




Click on file structure list

in left column to see table

Here, click on “City”



MySQL: SELECT Commands

SELECT Name FROM City

and click Go

Note column names on right

Note commands on bottom




Result:

Names of cities




Select multiple columns

from tables using comma (,)

between column labels

Note semicolon at end of line

(most compilers will run command without semicolon if command is only 1 line)

SELECT Name, CountryCode FROM City;




Result:

Names of cities

AND

Names of Country Codes




Insert wildcard

character (*) to

retrieve all information

SELECT * FROM City




Result:

Entire dataset



MySQL: SELECT with Distinct and LIMIT

DISTINCT:

To show only one

instance of a particular

value

SELECT DISTINCT CountryCode FROM City



Result:

Distinct country codes




Show only first 5

using LIMIT command

SELECT Name, CountryCode FROM City LIMIT 5




Result: First 5 entries




Select only limited set of entries

From start point (say, 5)

To a certain number of data points (say, 10)

(Computers start counting at 0, not at 1,

so results will show “6”, not “5”

SELECT Name, CountryCode FROM City LIMIT 5, 10




Result: Results 5 - 15




Fully Qualified Names:

“dataset.label”

Handy if working on

multiple databases

with the same column

SELECT City.Name FROM City




Results: Same as before

Note names in order as

found in the original table;

Can be confusing.

Alternative: Sort.




MySQL: Sorting

Sort results using

ORDER BY command

SELECT Name FROM City ORDER BY Name



MySQL: Sorting

Results are now in

alphabetic order



MySQL: Sorting

Sorting multiple columns,

specifying order parameter

SELECT Name, CountryCode, District FROM City ORDER BY Name



MySQL: Sorting

Results:

Multiple columns,

sorted by Name



MySQL: Sorting

Sequential Sort:

Sort by x, then by y

SELECT Name,CountryCode,District from City ORDER BY name,CountryCode



MySQL: Sorting

Result:

Sort by Name,

then by Country Code

(not very interesting

in this case, because

data is unique for each area)



MySQL: Sorting

Sorting in reverse

direction; from high to low

DESC = Descending

ASC = Ascending

SELECT Name, CountryCode FROM City ORDER BY Name DESC



MySQL: Sorting

Result: Names from Z – A

BUT: Algorithm lists

special characters,

such as umlauted vowels,

AFTER Z



MySQL: Sorting

Select highest value

(or lowest value)

SELECT Name, Population FROM City ORDER BY Population LIMIT 1



MySQL: Sorting

Results:

Adamstown has the

smallest population,

with only 42 people



MySQL: Sorting

Select highest value

(or lowest value)

SELECT Name, Population FROM City ORDER BY Population DESC LIMIT 1



MySQL: Sorting

Results:

Mubai has the

largest population,

with 10,500,000 people



MySQL: Filtering

Filtering:

Want only areas

within country code ‘AFG’

SELECT Name, CountryCode FROM City WHERE CountryCode=‘AFG’



MySQL: Filtering

Results



MySQL: Filtering

Filtering:

Want to list

“small cities”,

i.e. areas

with population

under 10,000

SELECT Name, Population FROM City WHERE Population <= 10000

(could also show “large cities”) :

SELECT Name, Population FROM City WHERE Population >= 10000



MySQL: Filtering

Result:

Listing of “small” cities

in ID order

(could also sort if desired)



MySQL: Filtering

Filtering:

Want to list

“medium cities”

i.e. areas

with population

between

10,000 and 50,000: SELECT Name, Population FROM City WHERE Population BETWEEN 10000 AND 50000

OR

SELECT Name, Population FROM City WHERE Population >= 10000 && Population <= 50000



MySQL: Filtering

Result:

“Sweet spot” cities

between 10,000 and

50,000



MySQL: Logical Operators

Find name of city

within AFG with a

population greater

than 200,000

SELECT Name, CountryCode FROM City WHERE CountryCode=‘AFG’ AND Population>200000




Result: Two cities

met both criteria




Find name of city

within NLD

OR with a population

greater than 400,000

SELECT Name, CountryCode, Population

FROM City WHERE CountryCode=‘NLD’ AND Population>400000



MySQL Server

Result: Three cities

met at least one of the

criteria



MySQL: Searching

Use REGEXP

(regular expression)

to search for item.

Here, we want to

search for any district

with the word “Holland”

in it.

SELECT Name, District FROM City WHERE District REGEXP 'Holland'



MySQL: Searching

Results:

Many districts have

the word “Holland”

in them



MySQL: Special Columns

Create special columns

using math: +, -, *, /

For example, what if

population were to grow by 10%?

SELECT Name, Population, Population*1.1 AS Population_Growth FROM City



MySQL: Special Columns

Result:

Special Column temporarily

inserted in database:

Population Growth

Shows population + 10%

SELECT Name, Population, Population*1.1 AS Population_Growth FROM City



MySQL: Create Database

Create new database

called “database2”

CREATE DATABASE database2

To delete database:

DROP DATABASE database2



MySQL: Create Table

Create new table

through phpMyAdmin

By clicking on Database



MySQL: Create Table

Within phpMyAdmin:

Create table:

Enter Name

Enter number of columns



MySQL: Create Table

Within MySQL:

Create new table: CREATE

Drop or rename table:

DROP TABLE signup

RENAME TABLE signup TO users

Create new table

for website

where people can

sign up for emails

CREATE TABLE signup ( Open bracket; Create new lines

id int NOT NULL AUTO_INCREMENT First variable: id; data type: Integer; Automatically add 1

name varchar (30) NOT NULL Second variable: name; alphanumeric text; Required

email varchar (30) NOT NULL Third variable: email; max length: 30 char. ; Required

PRIMARY KEY (id) Declare primary key; in this case, “id”

) Close bracket



MySQL: Create Table

Click on Structure

to see table structure

id underlined

PRIMARY KEY



MySQL: Create Table

Manually enter data

by clicking Insert tab,

then click Go



MySQL Server

Results:

-Data inserted

-ID incremented

To Delete a Row:

DELETE FROM signup WHERE name = ‘Kathy Kar’



MySQL: Alter Table

Add column:

phone (phone number)

To add a column:

ALTER TABLE signup ADD phone varchar(10) NOT NULL

To delete a column:

ALTER TABLE signup DROP COLUMN phone



MySQL Server

Results:

New column inserted:

“phone”



MySQL: Reference Manuals

To learn all commands, functions, etc. available, go to:

dev.mysql.com/doc/index.html



Marketing Analytics - Stephan SorgerLogical Using logical commands (AND, OR) in commands Creating...

Documents

Transcript of Marketing Analytics - Stephan SorgerLogical Using logical commands (AND, OR) in commands Creating...