Thread: pgsql: Add an optional missing_ok argument to SQL function current_sett

Add an optional missing_ok argument to SQL function current_setting().

This allows convenient checking for existence of a GUC from SQL, which is
particularly useful when dealing with custom variables.

David Christensen, reviewed by Jeevan Chalke

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/10fb48d66de76e7dc1e36ef18af502ed9600352f

Modified Files
--------------
contrib/tsearch2/tsearch2.c       |    2 +-
doc/src/sgml/func.sgml            |    7 ++++-
src/backend/utils/misc/guc.c      |   53 +++++++++++++++++++++++++++++--------
src/include/catalog/catversion.h  |    2 +-
src/include/catalog/pg_proc.h     |    6 +++--
src/include/utils/builtins.h      |    1 +
src/include/utils/guc.h           |    3 ++-
src/test/regress/expected/guc.out |   31 ++++++++++++++++++++++
src/test/regress/sql/guc.sql      |   13 +++++++++
9 files changed, 101 insertions(+), 17 deletions(-)