[pgpool-committers: 5319] pgpool: Fix query cache invalidation bug.

[Tatsuo Ishii]

Fix query cache invalidation bug.

When a DML is executed in an explicit transaction, the table oid
buffer is wiped out by pool_reset_memqcache_buffer() and query cache
is not invalidated at the commit time because there's no DML oid
exists to invalidate query cache any more. To fix this, add new bool
parameter to pool_reset_memqcache_buffer() to specify whether to reset
table oid buffer or not. When a DML is executed in an explicit
transaction, call pool_reset_memqcache_buffer(false) to preserve the
table oid buffer.

Issue reported at https://github.com/pgpool/pgpool2/issues/19.

Branch
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V4_0_STABLE

Details
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https://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=e9db5422f1d03a95e335336a4da8b043aa490deb

Modified Files
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src/query_cache/pool_memqcache.c | 28 ++++++++++++++++------------
1 file changed, 16 insertions(+), 12 deletions(-)