Re: Streaming Replication: sql error on standby

On Wed, 2010-06-23 at 10:48 +0200, Sander, Ingo (NSN - DE/Munich) wrote:

> Sql query "select pg_last_xlog_receive_location(); " does not work
> during startup of standby database. 

Thanks for the report.

We need to understand more about what you are saying. There is no error
message with that text.

> TestScenario; 
> We have a active-standby system with PostgreSQL Streaming Replication
> beta2. If the active database is up the database is in use (read/write
> queries will be performed). Then the standby PostgreSQL SR will be
> started (the complete database from the active side is copied to the
> standby side; nec. Files for starting streaming replication are
> created). Directly after the possibility to connect to the standby
> system, the above given sql query will be executed. To this timepoint
> the sql query delivers an error. To a later timepoint (all wal
> segments are completly incooperated) the query delivers a valid
> result. 
> 
> Question: 
> What is the reason for the error? 
> Exists a command to find out if the standby database is really active
> to accept/can work with sql commands? 

Could you show us the log?

-- Simon Riggs           www.2ndQuadrant.comPostgreSQL Development, 24x7 Support, Training and Services