On 21/09/2011, at 9:39 AM, Craig Ringer wrote:

> On 21/09/2011 7:27 AM, Royce Ausburn wrote:
>> Hi all,
>> 
>> It looks like I've been hit with this well known issue.  I have a 
>> complicated query that is intended to run every few minutes, I'm using 
>> JDBC's Connection.prepareStatement() mostly for nice parameterisation, but 
>> postgres produces a suboptimal plan due to its lack of information when the 
>> statement is prepared.
>> 
>> [snip]
>> 
>> We've been worst hit by this query on an 8.3 site.  Another site is running 
>> 8.4.  Have there been improvements in this area recently?  Upgrading to 9.0 
>> might be viable for us.
> 
> Tom just mentioned that 9.1 will be able to re-plan parameterized prepared 
> statements, so this issue will go away. In the mean time you can only really 
> use the standard workaround of setting the prepare theshold to 0 to disable 
> server-side prepare, so you can continue to use JDBC prepared statements and 
> have the driver do the parameter substitution for you.

Thanks Craig -- that trick helps a lot.  

--Royce
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