howto force use of indices on one table

Moin,

I got a table with 10 float columns (a0 .. a9) and 600000 rows. I created indices for each column. But when I do a select (exact or range match) on 2 or more columns Oracle uses only one index.

At first all values per column were distinct. Than I tried only 4 diffrent values per column. So querying a concrete value in one column selects 1/4 of all. I expect Oracle using the index of the next column to get (1/4)/4 of all and so on, instead it does a full scan of 1/4.

My settings:
optimizer goal : first_rows
analyzed the table and each index

Can anyone tell me what I did wrong?

thx
  Sven Received on Fri May 28 1999 - 04:41:10 CDT