Locking: Matching up sessions

From: Ben Ryan <benryan_at_my-deja.com>
Date: Thu, 02 Sep 1999 19:20:43 GMT
Message-ID: <7qmils$vsk$1@nnrp1.deja.com>

Scenario involving just one table containing just three rows, which I will call r1, r2 and r3.

Imagine three sessions are each updating a single row in the table and none of them have yet commited the change. Call the sessions A, B and C. Let us say A is updating r1
B is updating r2
C is updating r3.

Imagine two more sessions called x and y. Which, are both trying to a update a single row in the table and they were both initiated after sessions A, B and C had acquired their locks. Lets us say that x is trying to update r1 and
y is trying to update r2.

By querying v$lock.id1 I can see how to say that some combination of sessions A, B and C are blocking sessions x and y.

Is there anyway to discover that
A is blocking x and
B is blocking y

Sent via Deja.com http://www.deja.com/
Share what you know. Learn what you don't. Received on Thu Sep 02 1999 - 14:20:43 CDT