[pgpool-committers: 4933] pgpool: Fist cut of disable load balance feature.

[Tatsuo Ishii]

Fist cut of disable load balance feature.

If write query is issued in an explicit transaction and
disable_load_balance is set to 'trans_transaction', then subsequent
read queries will be redirected to primary node even if the
transaction is closed.

TODO:

- Implement 'always' case. In addition to 'trans_transaction', the
  effect persists even outside of explicit transactions until the
  session ends.

- Documentation

Branches
--------
SCRAM_AUTH
master
query_cache

Details
-------
https://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=ba19a3830c2fed9169e2c65449c32790b399378c

Modified Files
--------------
src/config/pool_config_variables.c         | 18 ++++++++++++++++++
src/include/pool_config.h                  | 22 ++++++++++++++++++++++
src/protocol/CommandComplete.c             |  5 ++++-
src/protocol/pool_proto_modules.c          |  8 ++++++--
src/sample/pgpool.conf.sample              | 11 +++++++++++
src/sample/pgpool.conf.sample-master-slave | 11 +++++++++++
src/sample/pgpool.conf.sample-replication  | 11 +++++++++++
src/sample/pgpool.conf.sample-stream       | 11 +++++++++++
src/utils/pool_process_reporting.c         |  5 +++++
9 files changed, 99 insertions(+), 3 deletions(-)