pgsql: Disallow CREATE/DROP SUBSCRIPTION in transaction block

Disallow CREATE/DROP SUBSCRIPTION in transaction block

Disallow CREATE SUBSCRIPTION and DROP SUBSCRIPTION in a transaction
block when the replication slot is to be created or dropped, since that
cannot be rolled back.

based on patch by Masahiko Sawada <sawada(dot)mshk(at)gmail(dot)com>

Branch
------
master

Details
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http://git.postgresql.org/pg/commitdiff/272adf4f9cd67df323ae57ff3dee238b649d3b73

Modified Files
--------------
doc/src/sgml/ref/create_subscription.sgml | 5 ++++
doc/src/sgml/ref/drop_subscription.sgml | 4 ++--
src/backend/commands/subscriptioncmds.c | 38 +++++++++++++++++++++++-------
src/backend/tcop/utility.c | 5 ++--
src/include/commands/subscriptioncmds.h | 5 ++--
src/test/regress/expected/subscription.out | 12 ++++++++++
src/test/regress/sql/subscription.sql | 12 ++++++++++
7 files changed, 66 insertions(+), 15 deletions(-)