overlapping "select for update" statements

I'm not quiet sure how "select for update" works in the case that I execute a second "select for update" statement in the same process.

Imagine I have some records in a table locked by a first "select for update". Then I execute a second "select for update" on other records. In the case of strictly different records it will work without any problems I think.

But what, if the where clause of the second statement includes also records locked by the first statement? Does the second statement at least return (and lock) the remaining still unlocked records, does it wait until all records are unlocked or do I just get a runtime error?

T.M. Received on Thu Apr 20 2006 - 09:57:21 CDT