Tom Lane wrote:
> Bruce Momjian <[EMAIL PROTECTED]> writes:
> > I imagine folks would want it on UPDATE, DELETE, and VACUUM FULL too,
> Why?  You can do a SELECT FOR UPDATE first and then you know that you
> have the row lock.  There's no need for any special handling of UPDATE
> or DELETE.  I don't see the applicability to VACUUM, either.

Why bother when you can do it without the SELECT FOR UPDATE?

> BTW, one idea I was thinking about was that a SELECT FOR UPDATE NOWAIT
> behavior might simply not return the rows it couldn't acquire lock on,
> instead of erroring out.  Not sure if this would be more or less useful
> than the error behavior, but I can definitely think of possible
> applications for it.
> > Also, I don't see this changing sematics like the regex flavor did. 
> You're kidding.  This is a much more fundamental change of behavior than

No, I am not.

> whether some seldom-used regex features work.  In particular, we know
> that the regex behavior does not affect any other part of the system.
> I do not think any equivalent safety claims can be made for random
> hacking of whether LockAcquire succeeds or not.

It throws an error. I don't see how that could cause actual data
corruption or invalid data.

  Bruce Momjian                        |
  [EMAIL PROTECTED]               |  (610) 359-1001
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