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Hello
version: 10g,10.2.0.4,2 node rac
i have 2 tables
primary table is X and child table is z and column x_id is primary key referenced in table Z
table X is list partation by x_client_id
table X
====
x_id number,
x_client_id number,
x_search
x_date date
table z
=======
z_id
x_id
z_desc
z_datei am trying to delete rows from table X for client 9999 where the x_id doesnot present in table Z
delete from table_X where x_client_id =9999 and x_id not in (select x_id from table_z ) and TRUNC(x_date)='21-oct-2009' ;the above stmt works fine but delete taking long time for a day.it takes like 2+ minutes for 400 rows
index's:
=======
table x has index trunc(x_date)
table x has one index on two columns  x_client_id and x_search
table Z has index on x_id
tble x has one more child and in that x_id has primary keyhow can i improve further?
any help/ideas are appreciated
thank you
Edited by: nydba on Apr 3, 2011 3:48 PM

Answer 1

Did you try not exists.
What is the explain plan for not in vs not exists? Are the indexes being used?
DELETE FROM table_y y
      WHERE     x_client_id = 9999
            AND NOT EXISTS
                   (SELECT 1
                      FROM table_z z
                     WHERE z.XID = y.x_id)
            AND TRUNC (x_date) = '21-oct-2009';Post the explain plan for
SELECT * FROM table_y y
      WHERE     x_client_id = 9999
            AND NOT EXISTS
                   (SELECT 1
                      FROM table_z z
                     WHERE z.XID = y.x_id)
            AND TRUNC (x_date) = '21-oct-2009';And similarly for the not is statement.
G.