From 4e446563be720760efcb18e4a83b7189638f6ae8 Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Thu, 5 Jan 2017 11:33:51 -0500 Subject: [PATCH] Fix handling of empty arrays in array_fill(). array_fill(..., array[0]) produced an empty array, which is probably what users expect, but it was a one-dimensional zero-length array which is not our standard representation of empty arrays. Also, for no very good reason, it rejected empty input arrays; that case should be allowed and produce an empty output array. In passing, remove the restriction that the input array(s) have lower bound 1. That seems rather pointless, and it would have needed extra complexity to make the check deal with empty input arrays. Per bug #14487 from Andrew Gierth. It's been broken all along, so back-patch to all supported branches. Discussion: https://postgr.es/m/20170105152156.10135.64195@wrigleys.postgresql.org --- src/backend/utils/adt/arrayfuncs.c | 28 ++++++++-------------------- src/test/regress/expected/arrays.out | 27 +++++++++++++++++++++++++++ src/test/regress/sql/arrays.sql | 8 ++++++++ 3 files changed, 43 insertions(+), 20 deletions(-) diff --git a/src/backend/utils/adt/arrayfuncs.c b/src/backend/utils/adt/arrayfuncs.c index fb3ae1d307f..68f58b4692f 100644 --- a/src/backend/utils/adt/arrayfuncs.c +++ b/src/backend/utils/adt/arrayfuncs.c @@ -4956,25 +4956,19 @@ array_fill_internal(ArrayType *dims, ArrayType *lbs, /* * Params checks */ - if (ARR_NDIM(dims) != 1) + if (ARR_NDIM(dims) > 1) ereport(ERROR, (errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR), errmsg("wrong number of array subscripts"), errdetail("Dimension array must be one dimensional."))); - if (ARR_LBOUND(dims)[0] != 1) - ereport(ERROR, - (errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR), - errmsg("wrong range of array subscripts"), - errdetail("Lower bound of dimension array must be one."))); - if (array_contains_nulls(dims)) ereport(ERROR, (errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED), errmsg("dimension values cannot be null"))); dimv = (int *) ARR_DATA_PTR(dims); - ndims = ARR_DIMS(dims)[0]; + ndims = (ARR_NDIM(dims) > 0) ? ARR_DIMS(dims)[0] : 0; if (ndims < 0) /* we do allow zero-dimension arrays */ ereport(ERROR, @@ -4988,24 +4982,18 @@ array_fill_internal(ArrayType *dims, ArrayType *lbs, if (lbs != NULL) { - if (ARR_NDIM(lbs) != 1) + if (ARR_NDIM(lbs) > 1) ereport(ERROR, (errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR), errmsg("wrong number of array subscripts"), errdetail("Dimension array must be one dimensional."))); - if (ARR_LBOUND(lbs)[0] != 1) - ereport(ERROR, - (errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR), - errmsg("wrong range of array subscripts"), - errdetail("Lower bound of dimension array must be one."))); - if (array_contains_nulls(lbs)) ereport(ERROR, (errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED), errmsg("dimension values cannot be null"))); - if (ARR_DIMS(lbs)[0] != ndims) + if (ndims != ((ARR_NDIM(lbs) > 0) ? ARR_DIMS(lbs)[0] : 0)) ereport(ERROR, (errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR), errmsg("wrong number of array subscripts"), @@ -5023,12 +5011,12 @@ array_fill_internal(ArrayType *dims, ArrayType *lbs, lbsv = deflbs; } - /* fast track for empty array */ - if (ndims == 0) - return construct_empty_array(elmtype); - nitems = ArrayGetNItems(ndims, dimv); + /* fast track for empty array */ + if (nitems <= 0) + return construct_empty_array(elmtype); + /* * We arrange to look up info about element type only once per series of * calls, assuming the element type doesn't change underneath us. diff --git a/src/test/regress/expected/arrays.out b/src/test/regress/expected/arrays.out index 89f1be3318a..104523c2afb 100644 --- a/src/test/regress/expected/arrays.out +++ b/src/test/regress/expected/arrays.out @@ -1295,16 +1295,43 @@ select array_fill('juhu'::text, array[3,3]); {{juhu,juhu,juhu},{juhu,juhu,juhu},{juhu,juhu,juhu}} (1 row) +select a, a = '{}' as is_eq, array_dims(a) + from (select array_fill(42, array[0]) as a) ss; + a | is_eq | array_dims +----+-------+------------ + {} | t | +(1 row) + +select a, a = '{}' as is_eq, array_dims(a) + from (select array_fill(42, '{}') as a) ss; + a | is_eq | array_dims +----+-------+------------ + {} | t | +(1 row) + +select a, a = '{}' as is_eq, array_dims(a) + from (select array_fill(42, '{}', '{}') as a) ss; + a | is_eq | array_dims +----+-------+------------ + {} | t | +(1 row) + -- raise exception select array_fill(1, null, array[2,2]); ERROR: dimension array or low bound array cannot be null select array_fill(1, array[2,2], null); ERROR: dimension array or low bound array cannot be null +select array_fill(1, array[2,2], '{}'); +ERROR: wrong number of array subscripts +DETAIL: Low bound array has different size than dimensions array. select array_fill(1, array[3,3], array[1,1,1]); ERROR: wrong number of array subscripts DETAIL: Low bound array has different size than dimensions array. select array_fill(1, array[1,2,null]); ERROR: dimension values cannot be null +select array_fill(1, array[[1,2],[3,4]]); +ERROR: wrong number of array subscripts +DETAIL: Dimension array must be one dimensional. select string_to_array('1|2|3', '|'); string_to_array ----------------- diff --git a/src/test/regress/sql/arrays.sql b/src/test/regress/sql/arrays.sql index d9f7cbfa8d2..54b0be7a7d7 100644 --- a/src/test/regress/sql/arrays.sql +++ b/src/test/regress/sql/arrays.sql @@ -383,11 +383,19 @@ select array_fill(7, array[3,3],array[2,2]); select array_fill(7, array[3,3]); select array_fill('juhu'::text, array[3,3],array[2,2]); select array_fill('juhu'::text, array[3,3]); +select a, a = '{}' as is_eq, array_dims(a) + from (select array_fill(42, array[0]) as a) ss; +select a, a = '{}' as is_eq, array_dims(a) + from (select array_fill(42, '{}') as a) ss; +select a, a = '{}' as is_eq, array_dims(a) + from (select array_fill(42, '{}', '{}') as a) ss; -- raise exception select array_fill(1, null, array[2,2]); select array_fill(1, array[2,2], null); +select array_fill(1, array[2,2], '{}'); select array_fill(1, array[3,3], array[1,1,1]); select array_fill(1, array[1,2,null]); +select array_fill(1, array[[1,2],[3,4]]); select string_to_array('1|2|3', '|'); select string_to_array('1|2|3|', '|');