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Computer Science

What is the difference between Candidate key and Alternate key?

SQL Queries

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Answer

Alternate Key	Candidate Key
A candidate key refers to all the attributes in a relation that are candidates or are capable of becoming a primary key.	Any attribute which is capable of becoming a primary key but is not a primary key is called an alternate key.

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Related Questions

Write SQL Commands for (i) to (v) and write the outputs for (vi) to (viii) on the basis of the following table:
Table: FURNITURE
NO ITEM TYPE DATEOFSTOCK PRICE DISCOUNT
1 White Lotus DoubleBed 2002-02-23 3000 25
2 Pinkfeathers BabyCot 2002-01-29 7000 20
3 Dolphin BabyCot 2002-02-19 9500 20
4 Decent OfficeTable 2002-02-01 25000 30
5 Comfortzone DoubleBed 2002-02-12 25000 30
6 Donald BabyCot 2002-02-24 6500 15
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(ii) To list the Item name and Price of furniture whose discount is between 10 and 20.
(iii) To delete the record of all items where discount is 30.
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(vi) SELECT DISTINCT Type FROM Furniture;
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(viii) SELECT COUNT(*) FROM Furniture WHERE Discount < 25 ;

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Table: GRADUATE
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2 RAJ 450 CHEMISTRY 68 1
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