Horton

Re: Proposal: Implement failover on libpq connect level.

Tatsuo Ishii <ishii@postgresql.org>

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From: Tatsuo Ishii <ishii@postgresql.org>
To: vitus@wagner.pp.ru
Cc: pgsql-hackers@postgresql.org
Date: 2015-08-19T03:42:45Z
Lists: pgsql-hackers 
I wonder how extended protocol is handled by this proposal. Suppose
load balacing mode is enabled. PQprepare is executed on standby1. Then
PQexecPrepared gets called. This may be executed on standby2, which
will fail because there's no prepared statement created by the former
PQprepare call.

Even simple procotol is used, same thing can be said to SQL
PREPARE/EXECUTE/DEALLOCATE.

SQL BEGIN/COMMIT/ROLLBACK would be more interesting example in load
balancing mode.

Best regards,
--
Tatsuo Ishii
SRA OSS, Inc. Japan
English: http://www.sraoss.co.jp/index_en.php
Japanese:http://www.sraoss.co.jp

Commits

  1. libpq: Add target_session_attrs parameter.

  2. Remove superuser checks in pgstattuple

  3. Fix unwanted flushing of libpq's input buffer when socket EOF is seen.