CREATE TABLE PLANTEST(A NUMBER, B VARCHAR2(10))Now I have created two non-unique indexes, for both the columns separately.
CREATE INDEX IND ON PLANTEST(A) CREATE INDEX IND_B ON PLANTEST(B)Now when I execute the below query, Oracle is hitting the index and fetching the values.
SELECT A FROM PLANTEST WHERE A = 3But when I execute the below query, the system is not hitting the index. Can you please tell me how I should change my index/query so that the index is hit?
SELECT A, B FROM PLANTEST WHERE A = 3 (nor) SELECT B FROM PLANTEST WHERE A = 3 --> Not Hitting IndexAs with prior queries, this is for character queries.
SELECT B FROM PLANTEST WHERE B LIKE 'A%' SELECT A FROM PLANTEST WHERE B LIKE 'A%' --> Full Table Scan
What makes you believe it is not hitting the index? It is probably using the index to find the table ROWIDS then...
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hitting the table to find the values not in the index. Try a concatenated index.
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