pgsql: Adjust psql \d query to avoid use of @> operator.

Adjust psql \d query to avoid use of @> operator.

It seems that the parray_gin extension has seen fit to introduce a
"text[] @> text[]" operator, which conflicts with the core
"anyarray @> anyarray" operator, causing ambiguous-operator failures
if the input arguments are coercible to text[] without being exactly
that type. This strikes me as a bad idea, but it's out there and
people use it. As of v10, that breaks psql's query that tries to
test "pg_statistic_ext.stxkind @> '{d}'", since stxkind is char[].
The best workaround seems to be to avoid use of that operator.
We can use a scalar-vs-array test "'d' = any(stxkind)" instead;
that's arguably more readable anyway.

Per report from Justin Pryzby. Backpatch to v10 where this
query was added.

Discussion: https://postgr.es/m/20171022181525.GA21884@telsasoft.com

Branch
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REL_10_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/852e3224e76e55f7e2046643d98d7d0786439a9c

Modified Files
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src/bin/psql/describe.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)