Changing table statistics

[issacgeorge]

Hai every body,
I've a table with a five column PK. The table now has only 20 rows. But its supposed to grow to lakhs or records. In the where clause of a query on this table, i'll be specifying first 4 columns of the PK. Still its going for a full table scan instead of a range scan. May be with a lot of records .. it might go for an index rnage scan.

My doubt is that .. are there any ways to set the table statistics. Means, can I alter the table statistics and say the table contains 10 lakh records.

So that i can see how the query behaves with 10 lakh records.

regards
Issac

[ales]

Hi,
yes, it is possible to change the statistics. In the dbms_stats package, there are the set_table_stats, set_index_stats and set column_stats procedures. You can play with them but I doubt you get anything useful. It's not only the number of rows that affect the optimizer, there is a lot of another parameters.

The far best method is to populate the table with rows, compute statistics and then test the query.

[issacgeorge]

Thanks Ales,

let me ponder over it...

regards
Issac