Thread: 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 oncereturn "record locked" after a specified
timeoutwaitfor 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 lockedset lock mode to wait 10;      -- wait at max 10 secondsset lock mode to wait;
      -- wait indefinitely
 

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

Andreas

> 
> > 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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