
> I don't know of any SQL databases that allow non-blocking lock requests.
> 
Informix has all kinds of non blocking locks:
	return "record locked" at once
	return "record locked" after a specified timeout
	wait for the lock indefinitely

To supply this behavior it has the following statements:
	set lock mode to not wait;	-- return immediately with error 
					-- if record already locked
	set lock mode to wait 10;  	-- wait at max 10 seconds
	set lock mode to wait;		-- wait indefinitely

Dirty read isolation has actually nothing to do with the wanted feature.

Andreas

Tue, 1 Jun 1999 10:03:10 +0200 
ZEUGSWETTER Andreas IZ5 <Andreas.Zeugswetter@telecom.at>
Re: [HACKERS] please? (non blocking lock)
> 
> > I don't know of any SQL databases that allow non-blocking lock requests.
> > 
> Informix has all kinds of non blocking locks:
> 	return "record locked" at once
> 	return "record locked" after a specified timeout
> 	wait for the lock indefinitely
> 
> To supply this behavior it has the following statements:
> 	set lock mode to not wait;	-- return immediately with error 
> 					-- if record already locked
> 	set lock mode to wait 10;  	-- wait at max 10 seconds
> 	set lock mode to wait;		-- wait indefinitely
> 
> Dirty read isolation has actually nothing to do with the wanted feature.

Oh, that's nice.  I never looked at those commands before.

-- 
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  maillist@candle.pha.pa.us            |  (610) 853-3000
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Tue, 1 Jun 1999 10:32:59 -0400 (EDT)
Bruce Momjian <maillist@candle.pha.pa.us>
Re: [HACKERS] please? (non blocking lock)