SQL Tutorial : INDEXES

SQL Tutorial : INDEXES

Let's learn about next topic: INDEXES

INDEXES:

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- USED FOR IMPROVING THE PERFORMANCE BY FETCHING THE

DATA FASTER

BASIC TYPES:

1.B-TREE INDEX

2.BIT MAP INDEX

- WHEN A PRIMARY KEY AND UNIQUE KEY CONSTRAINTS ARE CREATED

AUTOMATICALLY UNIQUE INDEX IS CREATED

NON -UNIQUE INDEX:

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- CREATE INDEX EMP_INX

ON EMPLOYEES

(LAST_NAME)

FUNCTION BASED INDEX:

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- CREATE INDEX EMP_INX

ON EMPLOYEES

INITCAP (LAST_NAME)

Dropping an Index:

DROP INDEX EMP_INX

DD: USER_INDEXES