pgsql: Rename columns in new pg_statistic_ext catalog

Rename columns in new pg_statistic_ext catalog

The new catalog reused a column prefix "sta" from pg_statistic, but this
is undesirable, so change the catalog to use prefix "stx" instead.
Also, rename the column that lists enabled statistic kinds as "stxkind"
rather than "enabled".

Discussion: https://postgr.es/m/CAKJS1f_2t5jhSN7huYRFH3w3rrHfG2QU7hiUHsu-Vdjd1rYT3w@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/ee6922112e9b3c02b995bd1d838c9a261f060133

Modified Files
--------------
doc/src/sgml/catalogs.sgml | 22 ++++++++++---------
doc/src/sgml/planstats.sgml | 4 ++--
src/backend/catalog/aclchk.c | 2 +-
src/backend/catalog/heap.c | 8 +++----
src/backend/catalog/objectaddress.c | 12 +++++-----
src/backend/commands/statscmds.c | 32 +++++++++++++--------------
src/backend/optimizer/util/plancat.c | 4 ++--
src/backend/statistics/dependencies.c | 4 ++--
src/backend/statistics/extended_stats.c | 34 ++++++++++++++---------------
src/backend/statistics/mvdistinct.c | 2 +-
src/backend/utils/adt/ruleutils.c | 18 +++++++--------
src/backend/utils/cache/relcache.c | 4 ++--
src/backend/utils/cache/syscache.c | 4 ++--
src/bin/pg_dump/pg_dump.c | 20 ++++++++---------
src/bin/psql/describe.c | 14 ++++++------
src/include/catalog/catversion.h | 2 +-
src/include/catalog/indexing.h | 4 ++--
src/include/catalog/pg_statistic_ext.h | 34 ++++++++++++++---------------
src/test/regress/expected/alter_generic.out | 8 +++----
src/test/regress/expected/stats_ext.out | 30 ++++++++++++-------------
src/test/regress/sql/alter_generic.sql | 6 ++---
src/test/regress/sql/stats_ext.sql | 14 ++++++------
22 files changed, 142 insertions(+), 140 deletions(-)