1 SELECT statement. 2 Sample database Supplier Part supplies (0,n) colour s# snamep# pname amount...

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SELECT statementSELECT statement

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• Sample database• Sample database

Supplier Part

supplies

(0,n) (0,n)

colours# sname p# pnameamount

city dob price qualitydate

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• Sample database

Supplier( s#, sname, city, dob )

• Sample database


primary key

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• Sample database


Part( p#, pname, colour, weight, quality )

• Sample database



primary key

primary key

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• Sample database


SP( s#, p#, sdate, amount )


• Sample database




primary key

primary key

primary key

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• Sample database




• Sample database




primary key

primary key

primary key

foreign key

foreign key

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• Sample database




• Sample database




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• SELECT statement template• SELECT statement template

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• SELECT statement template

SELECT < names of attributes >


SELECT < names of attributes >

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SELECT <names of attributes>

FROM <names of relational tables>




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WHERE <condition>




WHERE <condition>

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• Basic query• Basic query

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• Basic query

“Find full information about all suppliers”

• Basic query


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• Basic query


SELECT s#, sname, city, dob

FROM Supplier

or

• Basic query



FROM Supplier

or

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• Basic query



FROM Supplier

or

SELECT *

FROM Supplier;

• Basic query



FROM Supplier

or

SELECT *

FROM Supplier;

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• Projection query• Projection query

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• Projection query

“Find the numbers, names, and prices of all parts”



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SELECT p#, pname, price

FROM Part;



SELECT p#, pname, price

FROM Part;

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• Projection query with duplicates• Projection query with duplicates

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• Projection query with duplicates

“Find the numbers of all suppliers that shipped at least one part”



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SELECT s#

FROM SP;



SELECT s#

FROM SP;

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• Projection query with no duplicates• Projection query with no duplicates

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• Projection query with no duplicates




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SELECT DISTINCT s#

FROM SP;



SELECT DISTINCT s#

FROM SP;

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• Queries with standard functions• Queries with standard functions

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• Queries with standard functions

“Find the total number of shipments”



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SELECT count(*)

FROM SP;



SELECT count(*)

FROM SP;

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“Find the total number of all parts shipped”



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SELECT sum(quantity)

FROM SP;



SELECT sum(quantity)

FROM SP;

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“Find an average price of all parts”



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SELECT avg(price)

FROM Part;



SELECT avg(price)

FROM Part;

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“Find the highest and the lowest price”



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SELECT max(price), min(price)

FROM Part;



SELECT max(price), min(price)

FROM Part;

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• Queries with elementary condition• Queries with elementary condition

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• Queries with elementary condition

“Find the names and numbers of all gold parts”



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SELECT p#, pname

FROM Part

WHERE colour = ‘gold’;



SELECT p#, pname

FROM Part

WHERE colour = ‘gold’;

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“Find the names and dates of birth of all suppliers born before 1960”



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SELECT sname, dob

FROM Supplier

WHERE dob < ‘1-Jan-1960’;



SELECT sname, dob

FROM Supplier

WHERE dob < ‘1-Jan-1960’;

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“Find full information about all suppliers living in Paris “



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SELECT *

FROM Supplier

WHERE city = ‘Paris’;



SELECT *

FROM Supplier

WHERE city = ‘Paris’;

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“Find full information about all suppliers whose name starts from letter ‘J’ “



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SELECT *

FROM Supplier

WHERE sname LIKE ‘J%’;



SELECT *

FROM Supplier

WHERE sname LIKE ‘J%’;

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“Find full information about all shipments done between 1990 and 1996”



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SELECT *

FROM SP

WHERE sdate BETWEEN ‘01-Jan-1990’ AND

31-Dec-1996’;



SELECT *

FROM SP

WHERE sdate BETWEEN ‘01-Jan-1990’ AND

31-Dec-1996’;

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• Queries with Boolean expression• Queries with Boolean expression

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• Queries with Boolean expression

“Find the prices of all bolts that cost more than 50.0”



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SELECT price

FROM Part

WHERE (pname = ‘bolt’) AND

(price > 50.0);



SELECT price

FROM Part


(price > 50.0);

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“Find the prices of all gold or silver bolts”



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SELECT price

FROM Part


( (colour = ‘gold’) OR

(colour = ‘silver’));



SELECT price

FROM Part


( (colour = ‘gold’) OR

(colour = ‘silver’));

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SELECT price

FROM Part


(colour in (‘gold’, ‘silver’));



SELECT price

FROM Part


(colour in (‘gold’, ‘silver’));

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“Find the prices of all bolts except gold and silver”



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SELECT price

FROM Part


(colour NOT IN (‘gold’, ‘silver’));



SELECT price

FROM Part


(colour NOT IN (‘gold’, ‘silver’));

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“Find the prices of all parts except silver bolts”



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SELECT price

FROM Part

WHERE NOT( (pname = ‘bolt’) AND

(colour = ‘silver’) );



SELECT price

FROM Part

WHERE NOT( (pname = ‘bolt’) AND

(colour = ‘silver’) );

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SELECT price

FROM Part

WHERE (pname <> ‘bolt’) OR

(colour <> ‘silver’);



SELECT price

FROM Part

WHERE (pname <> ‘bolt’) OR

(colour <> ‘silver’);

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• Sorting• Sorting

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• Sorting

“Find all suppliers sorted by names in ascending order

• Sorting


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• Sorting


SELECT *

FROM Supplier

ORDER BY sname ASC;

• Sorting


SELECT *

FROM Supplier

ORDER BY sname ASC;

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• Sorting

“Find all parts sorted by prices in descending order”

• Sorting


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• Sorting


SELECT *

FROM Part

ORDER BY price DESC;

• Sorting


SELECT *

FROM Part

ORDER BY price DESC;

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• Queries with NULL values• Queries with NULL values

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• Queries with NULL values

“Find full information about all suppliers with unknown date of birth”



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SELECT *

FROM Supplier

WHERE dob IS NULL;



SELECT *

FROM Supplier

WHERE dob IS NULL;

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“Find full information about all suppliers with known date of birth”



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SELECT *

FROM Supplier

WHERE dob IS NOT NULL;



SELECT *

FROM Supplier

WHERE dob IS NOT NULL;

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• Bibliography

R. K. Stephens, et al. Teach Yourself SQL in 21 Days, day 9, week 2

P. O’Neil, Database - Principles, Programming, Performance, chapter 3.3

R. Elmasri, S.B. Navathe, Fundamentals of Database Systems, chapter .2

• Bibliography

R. K. Stephens, et al. Teach Yourself SQL in 21 Days, day 9, week 2

P. O’Neil, Database - Principles, Programming, Performance, chapter 3.3

R. Elmasri, S.B. Navathe, Fundamentals of Database Systems, chapter .2

1 SELECT statement. 2 Sample database Supplier Part supplies (0,n) colour s# snamep# pname amount...

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