Fix O(N^2) performance issue in pg_publication_tables view.
The original coding of this view relied on a correlated IN sub-query. Our planner is not very bright about correlated sub-queries, and even if it were, there's no way for it to know that the output of pg_get_publication_tables() is duplicate-free, making the de-duplicating semantics of IN unnecessary. Hence, rewrite as a LATERAL sub-query. This provides circa 100X speedup for me with a few hundred published tables (the whole regression database), and things would degrade as roughly O(published_relations * all_relations) beyond that. Because the rules.out expected output changes, force a catversion bump. Ordinarily we might not want to do that post-beta1; but we already know we'll be doing a catversion bump before beta2 to fix pg_statistic_ext issues, so it's pretty much free to fix it now instead of waiting for v13. Per report and fix suggestion from PegoraroF10. Discussion: https://postgr.es/m/1551385426763-0.post@n3.nabble.com
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@ -258,9 +258,10 @@ CREATE VIEW pg_publication_tables AS
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P.pubname AS pubname,
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P.pubname AS pubname,
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N.nspname AS schemaname,
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N.nspname AS schemaname,
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C.relname AS tablename
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C.relname AS tablename
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FROM pg_publication P, pg_class C
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FROM pg_publication P,
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JOIN pg_namespace N ON (N.oid = C.relnamespace)
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LATERAL pg_get_publication_tables(P.pubname) GPT,
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WHERE C.oid IN (SELECT relid FROM pg_get_publication_tables(P.pubname));
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pg_class C JOIN pg_namespace N ON (N.oid = C.relnamespace)
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WHERE C.oid = GPT.relid;
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CREATE VIEW pg_locks AS
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CREATE VIEW pg_locks AS
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SELECT * FROM pg_lock_status() AS L;
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SELECT * FROM pg_lock_status() AS L;
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@ -53,6 +53,6 @@
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*/
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*/
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/* yyyymmddN */
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/* yyyymmddN */
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#define CATALOG_VERSION_NO 201905141
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#define CATALOG_VERSION_NO 201905221
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#endif
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#endif
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@ -1441,10 +1441,10 @@ pg_publication_tables| SELECT p.pubname,
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n.nspname AS schemaname,
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n.nspname AS schemaname,
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c.relname AS tablename
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c.relname AS tablename
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FROM pg_publication p,
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FROM pg_publication p,
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LATERAL pg_get_publication_tables((p.pubname)::text) gpt(relid),
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(pg_class c
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(pg_class c
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JOIN pg_namespace n ON ((n.oid = c.relnamespace)))
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JOIN pg_namespace n ON ((n.oid = c.relnamespace)))
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WHERE (c.oid IN ( SELECT pg_get_publication_tables.relid
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WHERE (c.oid = gpt.relid);
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FROM pg_get_publication_tables((p.pubname)::text) pg_get_publication_tables(relid)));
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pg_replication_origin_status| SELECT pg_show_replication_origin_status.local_id,
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pg_replication_origin_status| SELECT pg_show_replication_origin_status.local_id,
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pg_show_replication_origin_status.external_id,
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pg_show_replication_origin_status.external_id,
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pg_show_replication_origin_status.remote_lsn,
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pg_show_replication_origin_status.remote_lsn,
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