From 4d6603f28dfc4a1cab0d7d317855d935e314297a Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Tue, 2 Jul 2019 12:32:49 -0400 Subject: [PATCH] Simplify psql \d's rule for ordering the indexes of a table. The previous rule was "primary key (if any) first, then other unique indexes in name order, then all other indexes in name order". But the preference for unique indexes seems a bit obsolete since the introduction of exclusion constraints. It's no longer the case that unique indexes are the only ones that constrain what data can be in the table, and it's hard to see what other rationale there is for separating out unique indexes. Other new features like the possibility for some indexes to be INVALID (hence, not constraining anything) make this even shakier. Hence, simplify the sort order to be "primary key (if any) first, then all other indexes in name order". No documentation change, since this was never documented anyway. A couple of existing regression test cases change output, though. Discussion: https://postgr.es/m/14422.1561474929@sss.pgh.pa.us --- src/bin/psql/describe.c | 2 +- src/test/regress/expected/alter_table.out | 8 ++++---- src/test/regress/expected/create_index.out | 10 +++++----- src/test/regress/expected/replica_identity.out | 12 ++++++------ 4 files changed, 16 insertions(+), 16 deletions(-) diff --git a/src/bin/psql/describe.c b/src/bin/psql/describe.c index 97167d2c4b..1c770b4347 100644 --- a/src/bin/psql/describe.c +++ b/src/bin/psql/describe.c @@ -2312,7 +2312,7 @@ describeOneTableDetails(const char *schemaname, " LEFT JOIN pg_catalog.pg_constraint con ON (conrelid = i.indrelid AND conindid = i.indexrelid AND contype IN ('p','u','x'))\n"); appendPQExpBuffer(&buf, "WHERE c.oid = '%s' AND c.oid = i.indrelid AND i.indexrelid = c2.oid\n" - "ORDER BY i.indisprimary DESC, i.indisunique DESC, c2.relname;", + "ORDER BY i.indisprimary DESC, c2.relname;", oid); result = PSQLexec(buf.data); if (!result) diff --git a/src/test/regress/expected/alter_table.out b/src/test/regress/expected/alter_table.out index e687150511..d621f61c62 100644 --- a/src/test/regress/expected/alter_table.out +++ b/src/test/regress/expected/alter_table.out @@ -1925,12 +1925,12 @@ create unique index on anothertab(f4); Indexes: "anothertab_pkey" PRIMARY KEY, btree (f1) "anothertab_f1_f4_key" UNIQUE CONSTRAINT, btree (f1, f4) - "anothertab_f2_key" UNIQUE CONSTRAINT, btree (f2) - "anothertab_f4_idx" UNIQUE, btree (f4) "anothertab_f2_f3_idx" btree (f2, f3) + "anothertab_f2_key" UNIQUE CONSTRAINT, btree (f2) "anothertab_f3_excl" EXCLUDE USING btree (f3 WITH =) "anothertab_f4_excl" EXCLUDE USING btree (f4 WITH =) WHERE (f4 IS NOT NULL) "anothertab_f4_excl1" EXCLUDE USING btree (f4 WITH =) WHERE (f5 > 0) + "anothertab_f4_idx" UNIQUE, btree (f4) alter table anothertab alter column f1 type bigint; alter table anothertab @@ -1950,12 +1950,12 @@ alter table anothertab alter column f5 type bigint; Indexes: "anothertab_pkey" PRIMARY KEY, btree (f1) "anothertab_f1_f4_key" UNIQUE CONSTRAINT, btree (f1, f4) - "anothertab_f2_key" UNIQUE CONSTRAINT, btree (f2) - "anothertab_f4_idx" UNIQUE, btree (f4) "anothertab_f2_f3_idx" btree (f2, f3) + "anothertab_f2_key" UNIQUE CONSTRAINT, btree (f2) "anothertab_f3_excl" EXCLUDE USING btree (f3 WITH =) "anothertab_f4_excl" EXCLUDE USING btree (f4 WITH =) WHERE (f4 IS NOT NULL) "anothertab_f4_excl1" EXCLUDE USING btree (f4 WITH =) WHERE (f5 > 0) + "anothertab_f4_idx" UNIQUE, btree (f4) drop table anothertab; create table another (f1 int, f2 text); diff --git a/src/test/regress/expected/create_index.out b/src/test/regress/expected/create_index.out index 5305b53cac..9305649c11 100644 --- a/src/test/regress/expected/create_index.out +++ b/src/test/regress/expected/create_index.out @@ -1374,10 +1374,10 @@ VACUUM FULL concur_heap; f1 | text | | | f2 | text | | | Indexes: - "concur_index2" UNIQUE, btree (f1) - "concur_index3" UNIQUE, btree (f2) INVALID "concur_heap_expr_idx" btree ((f2 || f1)) "concur_index1" btree (f2, f1) + "concur_index2" UNIQUE, btree (f1) + "concur_index3" UNIQUE, btree (f2) INVALID "concur_index4" btree (f2) WHERE f1 = 'a'::text "concur_index5" btree (f2) WHERE f1 = 'x'::text "std_index" btree (f2) @@ -1390,10 +1390,10 @@ REINDEX TABLE concur_heap; f1 | text | | | f2 | text | | | Indexes: - "concur_index2" UNIQUE, btree (f1) - "concur_index3" UNIQUE, btree (f2) "concur_heap_expr_idx" btree ((f2 || f1)) "concur_index1" btree (f2, f1) + "concur_index2" UNIQUE, btree (f1) + "concur_index3" UNIQUE, btree (f2) "concur_index4" btree (f2) WHERE f1 = 'a'::text "concur_index5" btree (f2) WHERE f1 = 'x'::text "std_index" btree (f2) @@ -2115,8 +2115,8 @@ WARNING: cannot reindex system catalogs concurrently, skipping all c2 | text | | | Indexes: "concur_reindex_ind1" PRIMARY KEY, btree (c1) - "concur_reindex_ind3" UNIQUE, btree (abs(c1)) "concur_reindex_ind2" btree (c2) + "concur_reindex_ind3" UNIQUE, btree (abs(c1)) "concur_reindex_ind4" btree (c1, c1, c2) Referenced by: TABLE "concur_reindex_tab2" CONSTRAINT "concur_reindex_tab2_c1_fkey" FOREIGN KEY (c1) REFERENCES concur_reindex_tab(c1) diff --git a/src/test/regress/expected/replica_identity.out b/src/test/regress/expected/replica_identity.out index 175ecd2879..739608aab4 100644 --- a/src/test/regress/expected/replica_identity.out +++ b/src/test/regress/expected/replica_identity.out @@ -85,13 +85,13 @@ SELECT relreplident FROM pg_class WHERE oid = 'test_replica_identity'::regclass; Indexes: "test_replica_identity_pkey" PRIMARY KEY, btree (id) REPLICA IDENTITY "test_replica_identity_expr" UNIQUE, btree (keya, keyb, (3)) + "test_replica_identity_hash" hash (nonkey) + "test_replica_identity_keyab" btree (keya, keyb) "test_replica_identity_keyab_key" UNIQUE, btree (keya, keyb) "test_replica_identity_nonkey" UNIQUE, btree (keya, nonkey) "test_replica_identity_partial" UNIQUE, btree (keya, keyb) WHERE keyb <> '3'::text "test_replica_identity_unique_defer" UNIQUE CONSTRAINT, btree (keya, keyb) DEFERRABLE "test_replica_identity_unique_nondefer" UNIQUE CONSTRAINT, btree (keya, keyb) - "test_replica_identity_hash" hash (nonkey) - "test_replica_identity_keyab" btree (keya, keyb) -- succeed, nondeferrable unique constraint over nonnullable cols ALTER TABLE test_replica_identity REPLICA IDENTITY USING INDEX test_replica_identity_unique_nondefer; @@ -115,13 +115,13 @@ SELECT relreplident FROM pg_class WHERE oid = 'test_replica_identity'::regclass; Indexes: "test_replica_identity_pkey" PRIMARY KEY, btree (id) "test_replica_identity_expr" UNIQUE, btree (keya, keyb, (3)) + "test_replica_identity_hash" hash (nonkey) + "test_replica_identity_keyab" btree (keya, keyb) "test_replica_identity_keyab_key" UNIQUE, btree (keya, keyb) REPLICA IDENTITY "test_replica_identity_nonkey" UNIQUE, btree (keya, nonkey) "test_replica_identity_partial" UNIQUE, btree (keya, keyb) WHERE keyb <> '3'::text "test_replica_identity_unique_defer" UNIQUE CONSTRAINT, btree (keya, keyb) DEFERRABLE "test_replica_identity_unique_nondefer" UNIQUE CONSTRAINT, btree (keya, keyb) - "test_replica_identity_hash" hash (nonkey) - "test_replica_identity_keyab" btree (keya, keyb) SELECT count(*) FROM pg_index WHERE indrelid = 'test_replica_identity'::regclass AND indisreplident; count @@ -163,13 +163,13 @@ SELECT relreplident FROM pg_class WHERE oid = 'test_replica_identity'::regclass; Indexes: "test_replica_identity_pkey" PRIMARY KEY, btree (id) "test_replica_identity_expr" UNIQUE, btree (keya, keyb, (3)) + "test_replica_identity_hash" hash (nonkey) + "test_replica_identity_keyab" btree (keya, keyb) "test_replica_identity_keyab_key" UNIQUE, btree (keya, keyb) "test_replica_identity_nonkey" UNIQUE, btree (keya, nonkey) "test_replica_identity_partial" UNIQUE, btree (keya, keyb) WHERE keyb <> '3'::text "test_replica_identity_unique_defer" UNIQUE CONSTRAINT, btree (keya, keyb) DEFERRABLE "test_replica_identity_unique_nondefer" UNIQUE CONSTRAINT, btree (keya, keyb) - "test_replica_identity_hash" hash (nonkey) - "test_replica_identity_keyab" btree (keya, keyb) Replica Identity: FULL ALTER TABLE test_replica_identity REPLICA IDENTITY NOTHING; -- 2.40.0