pgsql: Prevent log_replication_commands from causing SQL commands to be

Prevent log_replication_commands from causing SQL commands to be logged.

Commit 7c4f524 allowed walsender to execute normal SQL commands
to support table sync feature in logical replication. Previously
while log_statement caused such SQL commands to be logged,
log_replication_commands caused them to be logged, too.
That is, such SQL commands were logged twice unexpectedly
when those settings were both enabled.

This commit forces log_replication_commands to log only replication
commands, to prevent normal SQL commands from being logged twice.

Author: Masahiko Sawada
Reviewed-by: Kyotaro Horiguchi
Reported-by: Fujii Masao
Discussion: http://postgr.es/m/CAHGQGwFDWh_Qr-q_GEMpD+qH=vYPMdVqw=ZOSY3kX_Pna9R9SA@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/3a66581dd12b4108ce22fb4dad38258df39cb685

Modified Files
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src/backend/replication/walsender.c | 18 ++++++++++--------
1 file changed, 10 insertions(+), 8 deletions(-)