Thread: pgsql: Add a transform function for varbit typmod coercisions.

Add a transform function for varbit typmod coercisions.

This enables ALTER TABLE to skip table and index rebuilds when the
new type is unconstraint varbit, or when the allowable number of bits
is not decreasing.

Noah Misch, with review and a fix for an OID collision by me.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/f7d7dade8afe19847510efe44be191c35e1ce26c

Modified Files
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src/backend/utils/adt/varbit.c   |   35 +++++++++++++++++++++++++++++++++++
src/include/catalog/catversion.h |    2 +-
src/include/catalog/pg_proc.h    |    4 +++-
src/include/utils/varbit.h       |    1 +
4 files changed, 40 insertions(+), 2 deletions(-)