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Hi,
How can I know how many rows will be returned from the query
SELECT *
FROM table1 t1, table2 t2
where t1.column1 = t2.cloumn2;
I know it can be done by
SELECT count(*)
FROM table1 t1, table2 t2
where t1.column1 = t2.cloumn2;
But I don't want to touch the actual data to get the information. Is there any statistics about that, and where is it stored? How can I get it by program?
I am wondering how the optimizer works it out.
Thanks in advance.
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Received on Thu Oct 21 1999 - 00:11:53 CDT