[pgpool-committers: 7968] pgpool: Fix SI mode to acquire a snapshot with an internal transaction.

[Tatsuo Ishii]

Fix SI mode to acquire a snapshot with an internal transaction.

In SI mode a data modifying statement needs to start internal
transaction.  However it forgot to acquire a snapshot. This commit
fixes that in both simple query protocol and extended query protocol.

Branch
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V4_2_STABLE

Details
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https://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=af2d2c50a4baf98b0805d6feb06a577a034f86c2

Modified Files
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src/protocol/pool_process_query.c | 15 ++++----------
src/protocol/pool_proto_modules.c | 43 +++++++++++++++++++++++++++++++++------
2 files changed, 41 insertions(+), 17 deletions(-)