Best way to find the count of rows affected by a query

Question

Hi All,
Is there a way to find the row count without actually executing the SQL statement? The count need not be accurate but it should be within acceptable limits. I know we can use 'explain plan' for this. But the value in plan_table.cardinality is way out of the actual expected count.
We would appreciate any pointers and/or suggestions.
Thanks
Edited by: user779842 on May 4, 2011 2:21 AM

Answer 1

maybe you can try this
How to get estimated number of rows of query without running actual query :
CREATE OR REPLACE FUNCTION get_rows_number (sql_select VARCHAR2, sql_id VARCHAR2) RETURN NUMBER AS
rows_number NUMBER;
BEGIN
EXECUTE IMMEDIATE
‘EXPLAIN PLAN SET STATEMENT_ID = ‘||CHR(39) || sql_id || CHR(39)||’ FOR ‘ || sql_select;
SELECT t.cardinality
INTO rows_number
FROM plan_table T
WHERE statement_id = sql_id AND ID = 0;
RETURN rows_number;
END;hope it helps!