Index usage

[bhabani s pradhan]

Hi All,

Merry Christmas to all.

I have this interesting problem..

For this query index ind1 on (c1,c2) columns is getting used.
SELECT 'x' 
FROM tab ta
WHERE ta.c1='val1';
(gives index ind1 range scan)

But for

SELECT 'x' 
FROM tab ta
WHERE ta.c1='val1'
AND ta.c3 = 'val2';
(gives FTS)
index ind1 is not being used. c3 is a nonindexed column.

I have already tried index(ta ind1) , RULE hints.

The table and the index are analyzed.



What cud be the reason for that?



Regards,
B S Pradhan