pgsql: Support for GiST in get_equal_strategy_number()

Support for GiST in get_equal_strategy_number()

A WITHOUT OVERLAPS primary key or unique constraint is accepted as a
REPLICA IDENTITY, since it guarantees uniqueness. But subscribers
applying logical decoding messages would fail because there was not
support for looking up the equals operator for a gist index. This
fixes that: For GiST indexes we can use the stratnum GiST support
function.

Reviewed-by: Paul Jungwirth <pj(at)illuminatedcomputing(dot)com>
Reviewed-by: vignesh C <vignesh21(at)gmail(dot)com>
Discussion: https://www.postgresql.org/message-id/flat/CA+renyUApHgSZF9-nd-a0+OPGharLQLO=mDHcY4_qQ0+noCUVg(at)mail(dot)gmail(dot)com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/74edabce7a33f428371f0da6c0338837fd9ac55e

Modified Files
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src/backend/executor/execReplication.c | 10 ++++------
1 file changed, 4 insertions(+), 6 deletions(-)