[PERFORM] Incr/Decr Integer

2009-07-16 Thread William Scott Jordan

Hey all!

Is there a better way to increase or decrease the value of an integer 
than doing something like:


---
UPDATE the_table SET the_int = the_int + 1 WHERE the_id = 123 ;
---

We seem to be getting a lot of deadlocks using this method under heavy 
load.  Just wondering if we should be doing something different.


Thanks!

-William

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Re: [PERFORM] Incr/Decr Integer

2009-07-16 Thread Richard Huxton

William Scott Jordan wrote:

Hey all!

Is there a better way to increase or decrease the value of an integer 
than doing something like:



UPDATE the_table SET the_int = the_int + 1 WHERE the_id = 123 ;


No.

We seem to be getting a lot of deadlocks using this method under heavy 
load.  Just wondering if we should be doing something different.


You can't get deadlocks with that - it only references one table.

What is the purpose of this query - how are you using it?

--
  Richard Huxton
  Archonet Ltd

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Re: [PERFORM] Incr/Decr Integer

2009-07-16 Thread Kevin Grittner
William Scott Jordan wsjor...@brownpapertickets.com wrote: 
 
 We seem to be getting a lot of deadlocks using this method under
 heavy load.
 
Could you post the exact message from one of these?
(Copy and paste if possible.)
 
-Kevin

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