[pgpool-general: 1797] Re: Select AddGeometryColumn query failing on one backend - urgent help needed

[Tatsuo Ishii]

> Thanks Tatsua for your immediate response. 
> 
> AddGeometryColumn adds geometry column to the table and also registers this column in geography_columns table of postgis(extension of postgresql). 
> 
> Is there a way I can tell Pgpool that Select AddGeometryColumn is a writing function? 

Yes, you can use "black_function_list" in pgpool.conf. See the manual for more details.

> The thing that I would also like to know why would restarting postgresql service on broken node(where it was not creating 'geom' and 'geom_low' columns) would make everything fine even Select AddGeometryColumn is now working fine, not sure when it will break again. The error does shows up frequently though.
> 
> Your reply will be again appreciated...

Not sure without looking into pgpool log and PostgreSQL log after
PostgreSQL restarting. One possibilty is restarting PostgreSQL
triggers failover and you are running the system with only one
backend. The another theory is you are so lucky and AddGeometryColumn
executed on the other PostgreSQL this time (remeber pgpool randomly
selects one the PostgreSQL in load balance) thus the table on both
PostgreSQL now has the column.
--
Tatsuo Ishii
SRA OSS, Inc. Japan
English: http://www.sraoss.co.jp/index_en.php
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