[Pgpool-general] backend mismatch

[Tatsuo Ishii]

> i configured pgpool without much of a problem, and replication works 
> fine (at least master/slave). But very often i get this error.
> 
> 2009-07-02 15:26:27 ERROR: pid 3892: read_kind_from_backend: 1 th kind D 
> does not match with master or majority connection kind C
> 2009-07-02 15:26:27 ERROR: pid 3892: kind mismatch among backends. 
> Possible last query was: "SET DateStyle=ISO;SELECT oid, 
> pg_encoding_to_char(encoding) AS encoding, datlastsysoid
> FROM pg_database WHERE oid = 24629" kind details are: 0[C] 1[D]
> 
> maybe anyone has any ideas?
> Both servers have freshly installed Gentoo Linux on them with 
> Postgresql-8.3.4 and pgpool-II-2.2.2

There are 2 possible reasons:

- Multi statement(mulitple SQL statements conjuncted with ";") does
  not work with pgpool-II.

- Queries relying on OID does not work with pgpool-II.

I thought these are stated in the doc as limitations of pgpool-II.
--
Tatsuo Ishii
SRA OSS, Inc. Japan