[COMMITTERS] pgsql: Optimize query for information_schema.constraint_column_usage

Optimize query for information_schema.constraint_column_usage

The way the old query was written prevented some join optimizations
because the join conditions were hidden inside a CASE expression.  With
a large number of constraints, the query became unreasonably slow.  The
new query performs much better.

From: Alexey Bashtanov <bashtanov@imap.cc>
Reviewed-by: Ashutosh Bapat <ashutosh.bapat@enterprisedb.com>

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/e3a58c8835a2cd428b8534dd8df30a7cb96c976b

Modified Files
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src/backend/catalog/information_schema.sql | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)