From c367fc69bfbd7e515cf26d4499483b56319f05db Mon Sep 17 00:00:00 2001 From: Tomas Vondra Date: Mon, 16 Aug 2021 17:19:33 +0200 Subject: [PATCH 2/2] fix: identify single-attribute references --- src/backend/commands/statscmds.c | 23 +++++++++++++++++++++++ src/bin/pg_dump/t/002_pg_dump.pl | 2 +- src/test/regress/expected/stats_ext.out | 2 ++ src/test/regress/sql/stats_ext.sql | 1 + 4 files changed, 27 insertions(+), 1 deletion(-) diff --git a/src/backend/commands/statscmds.c b/src/backend/commands/statscmds.c index 4856f4b41d..63c7529635 100644 --- a/src/backend/commands/statscmds.c +++ b/src/backend/commands/statscmds.c @@ -33,6 +33,7 @@ #include "optimizer/optimizer.h" #include "statistics/statistics.h" #include "utils/builtins.h" +#include "utils/lsyscache.h" #include "utils/fmgroids.h" #include "utils/inval.h" #include "utils/memutils.h" @@ -258,6 +259,28 @@ CreateStatistics(CreateStatsStmt *stmt) nattnums++; ReleaseSysCache(atttuple); } + else if (IsA(selem->expr, Var)) + { + Var *var = (Var *) selem->expr; + TypeCacheEntry *type; + + /* Disallow use of system attributes in extended stats */ + if (var->varattno <= 0) + ereport(ERROR, + (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), + errmsg("statistics creation on system columns is not supported"))); + + /* Disallow data types without a less-than operator */ + type = lookup_type_cache(var->vartype, TYPECACHE_LT_OPR); + if (type->lt_opr == InvalidOid) + ereport(ERROR, + (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), + errmsg("column \"%s\" cannot be used in statistics because its type %s has no default btree operator class", + get_attname(relid, var->varattno, false), format_type_be(var->vartype)))); + + attnums[nattnums] = var->varattno; + nattnums++; + } else /* expression */ { Node *expr = selem->expr; diff --git a/src/bin/pg_dump/t/002_pg_dump.pl b/src/bin/pg_dump/t/002_pg_dump.pl index a4ee54d516..be1f3a5175 100644 --- a/src/bin/pg_dump/t/002_pg_dump.pl +++ b/src/bin/pg_dump/t/002_pg_dump.pl @@ -2811,7 +2811,7 @@ my %tests = ( create_sql => 'CREATE STATISTICS dump_test.test_ext_stats_expr ON (2 * col1) FROM dump_test.test_fifth_table', regexp => qr/^ - \QCREATE STATISTICS dump_test.test_ext_stats_expr ON ((2 * col1)) FROM dump_test.test_fifth_table;\E + \QCREATE STATISTICS dump_test.test_ext_stats_expr ON (2 * col1) FROM dump_test.test_fifth_table;\E /xms, like => { %full_runs, %dump_test_schema_runs, section_post_data => 1, }, diff --git a/src/test/regress/expected/stats_ext.out b/src/test/regress/expected/stats_ext.out index 4e52910df2..2d7d05057f 100644 --- a/src/test/regress/expected/stats_ext.out +++ b/src/test/regress/expected/stats_ext.out @@ -55,6 +55,8 @@ ERROR: duplicate expression in statistics definition CREATE STATISTICS tst (unrecognized) ON x, y FROM ext_stats_test; ERROR: unrecognized statistics kind "unrecognized" -- incorrect expressions +CREATE STATISTICS tst ON (y) FROM ext_stats_test; -- single column reference +ERROR: extended statistics require at least 2 columns CREATE STATISTICS tst ON y + z FROM ext_stats_test; -- missing parentheses ERROR: syntax error at or near "+" LINE 1: CREATE STATISTICS tst ON y + z FROM ext_stats_test; diff --git a/src/test/regress/sql/stats_ext.sql b/src/test/regress/sql/stats_ext.sql index d563c4654c..9cdc34e82c 100644 --- a/src/test/regress/sql/stats_ext.sql +++ b/src/test/regress/sql/stats_ext.sql @@ -41,6 +41,7 @@ CREATE STATISTICS tst ON (x || 'x'), (x || 'x'), (y + 1), (x || 'x'), (x || 'x') CREATE STATISTICS tst ON (x || 'x'), (x || 'x'), y FROM ext_stats_test; CREATE STATISTICS tst (unrecognized) ON x, y FROM ext_stats_test; -- incorrect expressions +CREATE STATISTICS tst ON (y) FROM ext_stats_test; -- single column reference CREATE STATISTICS tst ON y + z FROM ext_stats_test; -- missing parentheses CREATE STATISTICS tst ON (x, y) FROM ext_stats_test; -- tuple expression DROP TABLE ext_stats_test; -- 2.31.1