[pgpool-committers: 3222] pgpool: Adding new PGPOOL SET and PGPOOL RESET commands.

[Muhammad Usama]

Adding new PGPOOL SET and PGPOOL RESET commands.

This is the final patch for the feature to add the SHOW and SET commands for pgpool-II
configuration parameters, similar to the PostgreSQL's SET and SHOW commands for
GUC variables. Specifically, this patch adds the functionality in pgpool-II to set
and reset the value of config parameters for the current session, and for that it adds
a new syntax in the pgpool-II which is similar to PostgreSQL's SET and RESET variable
syntax with an addition of PGPOOL keyword at the start.

-- syntax:

PGPOOL SET config_var_name {TO|=} value;

PGPOOL RESET config_var_name;

PGPOOL RESET all;

For adding this new syntax the patch uses the same parse node structure VariableSetStmt
used by PostgreSQL SET and RESET commands but with the different node tag.
i.e. T_PgpoolVariableSetStmt instead of T_VariableSetStmt.
This is specifically done to make sure we make a minimum amount of changes in parser
imported from the PostgreSQL. Otherwise, keeping the parser of pgpool in-sync with
PostgreSQL would require more merging efforts.

Currently the values of the following 10 pgpool-II configuration parameters can be altered
using the PGPOOL SET/RESET commands

log_statement
log_per_node_statement
check_temp_table
check_unlogged_table
allow_sql_comments
client_idle_limit
log_error_verbosity
client_min_messages
log_min_messages
client_idle_limit_in_recovery

English documentation changes for the complete feature are also included.

Branch
------
master

Details
-------
http://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=b9955cee5a01f1a898554190a778ac66632121d3

Modified Files
--------------
doc/pgpool-en.html                         |   266 +-
src/config/pool_config_variables.c         |   135 +-
src/include/pool_config_variables.h        |     5 +-
src/include/utils/pool_process_reporting.h |     2 +-
src/parser/gram.c                          | 48652 +++++++++++++--------------
src/parser/gram.y                          |    15 +-
src/protocol/child.c                       |     3 +
src/protocol/pool_proto_modules.c          |    99 +
src/utils/pool_process_reporting.c         |    25 +-
9 files changed, 24760 insertions(+), 24442 deletions(-)