Oracle database indexes are very important for SQL performance tuning and they are crucial for SQL query optimization. SQL Performance Tuning recommend that you create Oracle index or indexes on some table fields which are used in where clause. We recommends also to do some tests, before you do code to production environment.
EXAMPLE:
SQL query (note field priority in WHERE clause):
SELECT *
FROM detail
WHERE priority = 2;
Create index:
For SQL query performance optimization we recommends to create oracle index on field priority.
CREATE INDEX TEST_USER.DETAIL_IDX ON TEST_USER.DETAIL
(PRIORITY)
LOGGING
TABLESPACE TEST_USER
PCTFREE 10
INITRANS 2
MAXTRANS 255
STORAGE (
INITIAL 64K
MINEXTENTS 1
MAXEXTENTS UNLIMITED
PCTINCREASE 0
BUFFER_POOL DEFAULT
)
NOPARALLEL;