Re: "truncate all"? - Mailing list pgsql-hackers

From Bruce Momjian
Subject Re: "truncate all"?
Date
Msg-id 200308242257.h7OMv8208148@candle.pha.pa.us
Whole thread Raw
In response to Re: "truncate all"?  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-hackers
TODO updated:
* Allow TRUNCATE ... CASCADE/RESTRICT

---------------------------------------------------------------------------

Tom Lane wrote:
> Robert Treat <xzilla@users.sourceforge.net> writes:
> > On Sun, 2003-08-17 at 00:42, Tom Lane wrote:
> >> To do anything else, you'd have to solve some locking and/or
> >> race-condition problems: rows could be inserted in the other table
> >> while the TRUNCATE runs.
> 
> > Seems like you'll have that issue with truncate all wont you? I guess
> > we'll assume that if you use the cascade statement you understand these
> > risks and accept them.
> 
> Yeah.  A TRUNCATE ALL would need exclusive lock on every table.  If
> there are any other transactions running, the odds of getting all those
> locks without deadlocking are pretty low.  TRUNCATE CASCADE would also
> have a risk of failing due to deadlock (but with fewer tables in play
> it'd have a smaller risk).  TRUNCATE RESTRICT should *not* create a
> deadlock risk IMHO, and that means it can't lock other tables.
> 
>             regards, tom lane
> 

--  Bruce Momjian                        |  http://candle.pha.pa.us pgman@candle.pha.pa.us               |  (610)
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