ku***@tumkurcity.com (Kumar) wrote in message news:<2f**************************@posting.google. com>...
Hi,
I have a table (TAB1) withi has 4 child tables on COL1 with DELETE
CASCADE.
When I delete any row in TAB1, it will delete corresponding rows on
all child tables.
SQL : delete from TAB1 where COL1 = 21
Explain shows the following :
Estimated Cost = 164650096.000000
Estimated Cardinality = 6440161.000000
Can anybody help me in tuning this please ?
Unless you run detailed stats against all the tables involved using
the runstats command, DB2 may not know how many rows match that value
in the child tables. Check the Command Reference manual to see what
syntax is needed for capturing the most detailed information possible
on the foreign key columns in the child tables.