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Session 3

Welcome: To session 3-the 8th. learning sequence “Relational algebra “Recap : In the previous learning sequence, we

discussed some example queries.Present learning: We shall explore the following

topic: - Another example Queries.xample Queries.

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Relational Algebra

Relational AlgebraRelational Algebra

A basic expression in the relational algebra consists of either one of the following: A relation in the database A constant relation

Relational Instances for the Relational Instances for the Purchasing SystemPurchasing System

The Supplier relation:

S-number S-name S-city

S100 Ahmed Amman

S200 Ali Jarash

S300 Kasim Irbid

S400 Jasim Aquaba

S500 Rana Amman

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The Part relation:

P-number

P-name

Color Price P-city

P1 TV Silver 300 Amman

P2 Camera Black 100 Jarash

P3 Video Black 200 Amman

P4 PC Silver 400 Irbid

P5 Printer Red 100 Irbid

P6 Scanner silver 150 Jarash

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The shipment relation:

S-number

P-number

Quantity

S100 P1 100

S100 P2 150

S100 P3 200

S100 P4 160

S100 P5 50

S100 P6 70

S200 P1 200

S200 P2 150

S300 P2 400

S400 P2 150

S400 P4 80

S500 P4 100

Example QueriesExample Queries Q1- Get supplier names for suppliers who supplying at least one silver part.

Example QueriesExample Queries Q1- Get supplier names for suppliers who supplying at least one silver part.

Temp1 P-color = ‘silver’ (Part)

Example QueriesExample Queries Q1- Get supplier names for suppliers who supplying at least one silver part.

Temp1 P-color = ‘silver’ (Part)

P-number

P-name

Color Price P-city

P1 TV Silver 300 Amman

P4 PC Silver 400 Irbid

P6 Scanner

silver 150 Jarash

Temp1

Example QueriesExample Queries Q1- Get supplier names for suppliers who supplying at least one silver part.

Temp1 P-color = ‘silver’ (Part)Temp2 Shipment Temp1

Example QueriesExample Queries Q1- Get supplier names for suppliers who supplying at least one silver part.

Temp1 P-color = ‘silver’ (Part)Temp2 Shipment Temp1

S-number P-number

Quantity

P-name Color Price P-city

S100 P1 100 TV Silver 300 Amman

S100 P4 160 PC Silver 400 Irbid

S100 P6 70 Scanner silver 150 Jarash

S200 P1 200 TV Silver 300 Amman

S400 P4 80 PC Silver 400 Irbid

S500 P4 100 PC Silver 400 Irbid

Tem

p2

Example QueriesExample Queries Q1- Get supplier names for suppliers who supplying at least one silver part.

Temp1 P-color = ‘silver’ (Part)Temp2 Shipment Temp1Temp3 S-number (Temp2)

S-number

S100

S200

S400

S500

Temp3

Example QueriesExample Queries Q1- Get supplier names for suppliers who supplying at least one silver part.

Temp1 P-color = ‘silver’ (Part)Temp2 Shipment Temp1Temp3 S-number (Temp2)

Temp4 Supplier Temp3

S-number S-name S-city

S100 Ahmed Amman

S200 Ali Jarash

S400 Jasim Aquaba

S500 Rana Amman

Temp4

Example QueriesExample Queries Q1- Get supplier names for suppliers who supplying at least one silver part.

Temp1 P-color = ‘silver’ (Part)Temp2 Shipment Temp1Temp3 S-number (Temp2)

Temp4 Supplier Temp3

Result S-name (Temp4)S-name

Ahmed

Ali

Jasim

Rana

Result

Example QueriesExample Queries Q2- Get supplier names and cities who supplying parts stored in Irbid.

Example QueriesExample Queries Q2- Get supplier names and cities who supplying parts stored in Irbid.

Temp1 P-city = ‘Irbid’ (Part)

Example QueriesExample Queries Q2- Get supplier names and cities who supplying parts stored in Irbid.

Temp1 P-city = ‘Irbid’ (Part)

P-number

P-name Color Price P-city

P4 PC Silver 400 Irbid

P5 Printer Red 100 Irbid

Temp1

Example QueriesExample Queries Q2- Get supplier names and cities who

supplying parts stored in Irbid.

Temp1 P-city = ‘Irbid’ (Part)Temp2 Shipment Temp1

S-number

P-number Quantity

P-name Color

Price P-city

S100 P4 160 PC Silver 400 Irbid

S100 P5 50 Printer Red 100 Irbid

S400 P4 80 PC Silver 400 Irbid

S500 P4 100 PC Silver 400 Irbid

Temp2

Example QueriesExample Queries Q2- Get supplier names and cities who

supplying parts stored in Irbid.

Temp1 P-city = ‘Irbid’ (Part)Temp2 Shipment Temp1Temp3 S-number (Temp2)

S-number

S100

S400

S500

Temp3

Example QueriesExample Queries Q2- Get supplier names and cities who

supplying parts stored in Irbid.

Temp1 P-city = ‘Irbid’ (Part)Temp2 Shipment Temp1Temp3 S-number (Temp2)

Temp4 Supplier Temp3

Example QueriesExample Queries Q2- Get supplier names and cities who

supplying parts stored in Irbid.

Temp1 P-city = ‘Irbid’ (Part)Temp2 Shipment Temp1Temp3 S-number (Temp2)

Temp4 Supplier Temp3

S-number S-name S-city

S100 Ahmed Amman

S400 Jasim Aquaba

S500 Rana Amman

Temp4

Example QueriesExample Queries Q2- Get supplier names and cities who

supplying parts stored in Irbid.

Temp1 P-city = ‘Irbid’ (Part)Temp2 Shipment Temp1Temp3 S-number (Temp2)

Temp4 Supplier Temp3

Result S-name , S-city (Temp4)

Example QueriesExample Queries Q2- Get supplier names and cities who

supplying parts stored in Irbid.

Temp1 P-city = ‘Irbid’ (Part)Temp2 Shipment Temp1Temp3 S-number (Temp2)

Temp4 Supplier Temp3

Result S-name , S-city (Temp4)

S-name S-city

Ahmed Amman

Jasim Aquaba

Rana Amman

Result

Example QueriesExample Queries Q3- Find supplier names for suppliers who supply all parts.

Example QueriesExample Queries Q3- Find supplier names for suppliers who supply all parts.

Temp1 P-number (Part)

Example QueriesExample Queries Q3- Find supplier names for suppliers who supply all parts.

Temp1 P-number (Part)

P-number

P1

P2

P3

P4

P5

P6

Temp1

Example QueriesExample Queries Q3- Find supplier names for suppliers who supply all parts.

Temp1 P-number (Part)

Temp2 S-number , P-number (Shipment)

Example QueriesExample Queries Q3- Find supplier names for suppliers who supply all parts.

Temp1 P-number (Part)

Temp2 S-number , P-number (Shipment)

S-number

P-number

S100 P1

S100 P2

S100 P3

S100 P4

S100 P5

S100 P6

S200 P1

S200 P2

S300 P2

S400 P2

S400 P4

S500 P4

Temp2

Example QueriesExample Queries Q3- Find supplier names for suppliers who supply all parts.

Temp1 P-number (Part)Temp2 S-number , P-number (Shipment)

Temp3 Temp2 Temp1

Example QueriesExample Queries Q3- Find supplier names for suppliers who supply all parts.

Temp1 P-number (Part)Temp2 S-number , P-number (Shipment)

Temp3 Temp2 Temp1

S-number

S100Temp3

Example QueriesExample Queries Q3- Find supplier names for suppliers who supply all parts.

Temp1 P-number (Part)Temp2 S-number , P-number (Shipment)

Temp3 Temp2 Temp1 Temp4 Supplier Temp3

Example QueriesExample Queries Q3- Find supplier names for suppliers who supply all parts.

Temp1 P-number (Part)Temp2 S-number , P-number (Shipment)

Temp3 Temp2 Temp1 Temp4 Supplier Temp3

S-number

S-name S-city

S100 Ahmed Amman

Temp4

Example QueriesExample Queries Q3- Find supplier names for suppliers who supply all parts.

Temp1 P-number (Part)Temp2 S-number , P-number (Shipment)

Temp3 Temp2 Temp1 Temp4 Supplier Temp3

Result S-name (Temp4)

Example QueriesExample Queries Q3- Find supplier names for suppliers who supply all parts.

Temp1 P-number (Part)Temp2 S-number , P-number (Shipment)

Temp3 Temp2 Temp1 Temp4 Supplier Temp3

Result S-name (Temp4)

S-name

AhmedResult

Example QueriesExample Queries Q4- How many parts they have?

Example QueriesExample Queries Q4- How many parts they have?

g count (P-number) (Part)

P-number

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Example QueriesExample Queries Q5- Find the total quantities supplied by each supplier.

Example QueriesExample Queries Q6- Find the total quantities supplied by each supplier.

S-number g sum (Quantity) (Shipment)

Example QueriesExample Queries Q6- Find the total quantities supplied by each supplier.

S-number g sum (Quantity) (Shipment)

S-number Quantity

S100 730

S200 350

S300 400

S400 250

S500 100

Example QueriesExample Queries Q6- Find the total quantities supplied by each supplier.

S-number g sum (Quantity) as ( sum-quantity) (Shipment)

S-number Sum-Quantity

S100 730

S200 350

S300 400

S400 250

S500 100

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Relational AlgebraRelational Algebra

Summary: In this learning sequence, we discussed

another example queries about purchasing system.

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END