From 6cca2e003c1e43d4b3369e8802c116cc89691fed Mon Sep 17 00:00:00 2001 From: Corey Huinker Date: Tue, 10 Nov 2026 16:14:56 -0500 Subject: [PATCH v2 1/3] Allow empty arrays as input for pg_restore_attribute_stats. The attribute statistic code required that most_common_vals and most_common_freqs arrays, among others, must be one dimensional, which ruled out the possiblity of empty arrays. This fix relaxes that requirement to allow for empty arrays , and then makes all array length tests aware that an empty array has no dimensions. Currently these checks only happen for most_common_vals and most_common_freqs, as those two arrays must have the same length. All other usages have no such requirement. This was reported on its own in Bug #19857, which was recognized as being the same problem as Bug #19842. This fix is provided on its own because it needs to be backported to 18, whereas 19857 only needs to be backported to 19. Reported-by: Atish Prakash <125atishprak@gmail.com> Reported-by: chunling qin <303677365@qq.com> Author: Corey Huinker Discussion: https://postgr.es/m/19842-6e808a09ff4b75d2@postgresql.org Discussion: https://postgr.es/m/19857-6e808a09ff4b75d2@postgresql.org Bug: #19842 Bug: #19857 Backpatch-through: 18 --- src/backend/statistics/attribute_stats.c | 4 +- src/backend/statistics/stat_utils.c | 8 ++-- src/test/regress/expected/stats_import.out | 52 +++++++++++++++++++++- src/test/regress/sql/stats_import.sql | 31 +++++++++++++ 4 files changed, 88 insertions(+), 7 deletions(-) diff --git a/src/backend/statistics/attribute_stats.c b/src/backend/statistics/attribute_stats.c index f4bb846e88f..027b90b8ea7 100644 --- a/src/backend/statistics/attribute_stats.c +++ b/src/backend/statistics/attribute_stats.c @@ -405,8 +405,8 @@ attribute_statistics_update_internal(Oid reloid, { ArrayType *vals_arr = DatumGetArrayTypeP(stavalues); ArrayType *nums_arr = DatumGetArrayTypeP(stanumbers); - int nvals = ARR_DIMS(vals_arr)[0]; - int nnums = ARR_DIMS(nums_arr)[0]; + int nvals = (ARR_NDIM(vals_arr) > 0) ? ARR_DIMS(vals_arr)[0] : 0; + int nnums = (ARR_NDIM(nums_arr) > 0) ? ARR_DIMS(nums_arr)[0] : 0; if (nvals != nnums) { diff --git a/src/backend/statistics/stat_utils.c b/src/backend/statistics/stat_utils.c index e8117ede407..7929a6b6827 100644 --- a/src/backend/statistics/stat_utils.c +++ b/src/backend/statistics/stat_utils.c @@ -64,7 +64,7 @@ stats_check_required_arg(FunctionCallInfo fcinfo, /* * Check that argument is either NULL or a one dimensional array with no - * NULLs. + * NULLs, or an empty array. * * If a problem is found, emit a WARNING, and return false. Otherwise return * true. @@ -81,7 +81,7 @@ stats_check_arg_array(FunctionCallInfo fcinfo, arr = DatumGetArrayTypeP(PG_GETARG_DATUM(argnum)); - if (ARR_NDIM(arr) != 1) + if (ARR_NDIM(arr) > 1) { ereport(WARNING, (errcode(ERRCODE_INVALID_PARAMETER_VALUE), @@ -622,11 +622,11 @@ statatt_build_stavalues(const char *staname, FmgrInfo *array_in, Datum d, Oid ty pfree(s); - if (ARR_NDIM(DatumGetArrayTypeP(result)) != 1) + if (ARR_NDIM(DatumGetArrayTypeP(result)) > 1) { ereport(WARNING, (errcode(ERRCODE_INVALID_PARAMETER_VALUE), - errmsg("\"%s\" must be a one-dimensional array", staname))); + errmsg("\"%s\" must be a one-dimensional array or empty", staname))); *ok = false; return (Datum) 0; } diff --git a/src/test/regress/expected/stats_import.out b/src/test/regress/expected/stats_import.out index 60a0f20b488..8f91dc3a70d 100644 --- a/src/test/regress/expected/stats_import.out +++ b/src/test/regress/expected/stats_import.out @@ -967,7 +967,7 @@ SELECT pg_catalog.pg_restore_attribute_stats( 'most_common_vals', '{{2,1},{3,4}}'::text, 'most_common_freqs', '{0.3,0.25,0.05,0.04}'::real[] ); -WARNING: "most_common_vals" must be a one-dimensional array +WARNING: "most_common_vals" must be a one-dimensional array or empty pg_restore_attribute_stats ---------------------------- f @@ -4324,6 +4324,56 @@ SELECT count(*) FROM pg_statistic s 0 (1 row) +-- Bug #19842/#19857 +SELECT * FROM pg_catalog.pg_restore_attribute_stats( + 'schemaname', 'stats_import', + 'relname', 'test', + 'attname', 'arange', + 'inherited', 'f'::boolean, + 'range_length_histogram', '{}'::text, + 'range_empty_frac', '1'::real); + pg_restore_attribute_stats +---------------------------- + t +(1 row) + +-- Bug #19842/#19857 - one empty mismatch +SELECT pg_catalog.pg_restore_attribute_stats( + 'schemaname', 'stats_import', + 'relname', 'test', + 'attname', 'id', + 'inherited', false::boolean, + 'most_common_vals', '{1,3}'::text, + 'most_common_freqs', '{}'::real[]); +WARNING: could not parse "most_common_vals": incorrect number of elements (same as "most_common_freqs" required) + pg_restore_attribute_stats +---------------------------- + f +(1 row) + +-- Bug #19842/#19857 - both empty +SELECT pg_catalog.pg_restore_attribute_stats( + 'schemaname', 'stats_import', + 'relname', 'test', + 'attname', 'id', + 'inherited', false::boolean, + 'most_common_vals', '{}'::text, + 'most_common_freqs', '{}'::real[]); + pg_restore_attribute_stats +---------------------------- + t +(1 row) + +SELECT most_common_vals, most_common_freqs +FROM pg_stats +WHERE schemaname = 'stats_import' +AND tablename = 'test' +AND attname = 'id'; + most_common_vals | most_common_freqs +------------------+------------------- + {} | {} +(1 row) + DROP SCHEMA stats_import CASCADE; NOTICE: drop cascades to 39 other objects DETAIL: drop cascades to view stats_import.pg_stats_stable diff --git a/src/test/regress/sql/stats_import.sql b/src/test/regress/sql/stats_import.sql index e537a9d6f67..5bcd86288bf 100644 --- a/src/test/regress/sql/stats_import.sql +++ b/src/test/regress/sql/stats_import.sql @@ -3063,4 +3063,35 @@ SELECT count(*) FROM pg_statistic s AND a.attnum = s.staattnum AND NOT a.attisdropped); +-- Bug #19842/#19857 +SELECT * FROM pg_catalog.pg_restore_attribute_stats( + 'schemaname', 'stats_import', + 'relname', 'test', + 'attname', 'arange', + 'inherited', 'f'::boolean, + 'range_length_histogram', '{}'::text, + 'range_empty_frac', '1'::real); +-- Bug #19842/#19857 - one empty mismatch +SELECT pg_catalog.pg_restore_attribute_stats( + 'schemaname', 'stats_import', + 'relname', 'test', + 'attname', 'id', + 'inherited', false::boolean, + 'most_common_vals', '{1,3}'::text, + 'most_common_freqs', '{}'::real[]); +-- Bug #19842/#19857 - both empty +SELECT pg_catalog.pg_restore_attribute_stats( + 'schemaname', 'stats_import', + 'relname', 'test', + 'attname', 'id', + 'inherited', false::boolean, + 'most_common_vals', '{}'::text, + 'most_common_freqs', '{}'::real[]); + +SELECT most_common_vals, most_common_freqs +FROM pg_stats +WHERE schemaname = 'stats_import' +AND tablename = 'test' +AND attname = 'id'; + DROP SCHEMA stats_import CASCADE; base-commit: 952bab8b74d40fcfd25e1949865c3907e676504e -- 2.56.0