Please Explain Explain Plan!

Hi:

        I am doing an explain plan as follows:

	explain plan set statement_id 'BADRI' into plan_table
	for select * from mytable;

Concern #1:

        My understanding is that the rows in the plan_table for that statement_id are actually deleted before the new rows are inserted. This way, when I do a select on the plan_table for my plan_id, I get my rows. However, I saw that the deletes were not taking place. How does my client differentiate between rows already there and the current rows?

Concern #2:

        If I issue the same statement_id on CLient 1 and on client 2, and if there are already rows in the plan_table for that statement_id, how does my client know which one to show when I do the select?

        For some reason, I think the query should lock since the client that issued the command first would be trying to insert the rows (and not committed yet) that the second client tries to delete.

Please clarify,

thanks a lot,

-Badri Received on Fri May 24 1996 - 00:00:00 CEST