From 29d2f86a312e0c2060d4482649b26e9c33b760b5 Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Wed, 24 Feb 2010 18:02:24 +0000 Subject: [PATCH] Allow zero-dimensional (ie, empty) arrays in contrib/ltree operations. The main motivation for changing this is bug #4921, in which it's pointed out that it's no longer safe to apply ltree operations to the result of ARRAY(SELECT ...) if the sub-select might return no rows. Before 8.3, the ARRAY() construct would return NULL, which might or might not be helpful but at least it wouldn't result in an error. Now it returns an empty array which results in a failure for no good reason, since the ltree operations are all perfectly capable of dealing with zero-element arrays. As far as I can find, these ltree functions are the only places where zero array dimensionality is rejected unnecessarily. Back-patch to 8.3 to prevent behavioral regression of queries that worked in older releases. --- contrib/ltree/_ltree_gist.c | 6 +++--- contrib/ltree/_ltree_op.c | 8 ++++---- contrib/ltree/lquery_op.c | 4 ++-- contrib/ltree/ltree_gist.c | 4 ++-- 4 files changed, 11 insertions(+), 11 deletions(-) diff --git a/contrib/ltree/_ltree_gist.c b/contrib/ltree/_ltree_gist.c index 15c4cc022d..4c0e7c25c0 100644 --- a/contrib/ltree/_ltree_gist.c +++ b/contrib/ltree/_ltree_gist.c @@ -1,5 +1,5 @@ /* - * $PostgreSQL: pgsql/contrib/ltree/_ltree_gist.c,v 1.26 2009/06/11 14:48:51 momjian Exp $ + * $PostgreSQL: pgsql/contrib/ltree/_ltree_gist.c,v 1.27 2010/02/24 18:02:24 tgl Exp $ * * * GiST support for ltree[] @@ -88,7 +88,7 @@ _ltree_compress(PG_FUNCTION_ARGS) int num = ArrayGetNItems(ARR_NDIM(val), ARR_DIMS(val)); ltree *item = (ltree *) ARR_DATA_PTR(val); - if (ARR_NDIM(val) != 1) + if (ARR_NDIM(val) > 1) ereport(ERROR, (errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR), errmsg("array must be one-dimensional"))); @@ -534,7 +534,7 @@ _arrq_cons(ltree_gist *key, ArrayType *_query) lquery *query = (lquery *) ARR_DATA_PTR(_query); int num = ArrayGetNItems(ARR_NDIM(_query), ARR_DIMS(_query)); - if (ARR_NDIM(_query) != 1) + if (ARR_NDIM(_query) > 1) ereport(ERROR, (errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR), errmsg("array must be one-dimensional"))); diff --git a/contrib/ltree/_ltree_op.c b/contrib/ltree/_ltree_op.c index f9e90e978d..02c96c05d4 100644 --- a/contrib/ltree/_ltree_op.c +++ b/contrib/ltree/_ltree_op.c @@ -1,5 +1,5 @@ /* - * $PostgreSQL: pgsql/contrib/ltree/_ltree_op.c,v 1.13 2009/06/11 14:48:51 momjian Exp $ + * $PostgreSQL: pgsql/contrib/ltree/_ltree_op.c,v 1.14 2010/02/24 18:02:24 tgl Exp $ * * * op function for ltree[] @@ -48,7 +48,7 @@ array_iterator(ArrayType *la, PGCALL2 callback, void *param, ltree **found) int num = ArrayGetNItems(ARR_NDIM(la), ARR_DIMS(la)); ltree *item = (ltree *) ARR_DATA_PTR(la); - if (ARR_NDIM(la) != 1) + if (ARR_NDIM(la) > 1) ereport(ERROR, (errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR), errmsg("array must be one-dimensional"))); @@ -148,7 +148,7 @@ _lt_q_regex(PG_FUNCTION_ARGS) bool res = false; int num = ArrayGetNItems(ARR_NDIM(_query), ARR_DIMS(_query)); - if (ARR_NDIM(_query) != 1) + if (ARR_NDIM(_query) > 1) ereport(ERROR, (errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR), errmsg("array must be one-dimensional"))); @@ -306,7 +306,7 @@ _lca(PG_FUNCTION_ARGS) ltree **a, *res; - if (ARR_NDIM(la) != 1) + if (ARR_NDIM(la) > 1) ereport(ERROR, (errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR), errmsg("array must be one-dimensional"))); diff --git a/contrib/ltree/lquery_op.c b/contrib/ltree/lquery_op.c index df4f0794f2..1059417e77 100644 --- a/contrib/ltree/lquery_op.c +++ b/contrib/ltree/lquery_op.c @@ -1,7 +1,7 @@ /* * op function for ltree and lquery * Teodor Sigaev - * $PostgreSQL: pgsql/contrib/ltree/lquery_op.c,v 1.14 2009/06/11 14:48:51 momjian Exp $ + * $PostgreSQL: pgsql/contrib/ltree/lquery_op.c,v 1.15 2010/02/24 18:02:24 tgl Exp $ */ #include "postgres.h" @@ -344,7 +344,7 @@ lt_q_regex(PG_FUNCTION_ARGS) bool res = false; int num = ArrayGetNItems(ARR_NDIM(_query), ARR_DIMS(_query)); - if (ARR_NDIM(_query) != 1) + if (ARR_NDIM(_query) > 1) ereport(ERROR, (errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR), errmsg("array must be one-dimensional"))); diff --git a/contrib/ltree/ltree_gist.c b/contrib/ltree/ltree_gist.c index d48ca8e1d4..46fccb1ee1 100644 --- a/contrib/ltree/ltree_gist.c +++ b/contrib/ltree/ltree_gist.c @@ -1,7 +1,7 @@ /* * GiST support for ltree * Teodor Sigaev - * $PostgreSQL: pgsql/contrib/ltree/ltree_gist.c,v 1.25 2009/06/11 14:48:51 momjian Exp $ + * $PostgreSQL: pgsql/contrib/ltree/ltree_gist.c,v 1.26 2010/02/24 18:02:24 tgl Exp $ */ #include "postgres.h" @@ -602,7 +602,7 @@ arrq_cons(ltree_gist *key, ArrayType *_query) lquery *query = (lquery *) ARR_DATA_PTR(_query); int num = ArrayGetNItems(ARR_NDIM(_query), ARR_DIMS(_query)); - if (ARR_NDIM(_query) != 1) + if (ARR_NDIM(_query) > 1) ereport(ERROR, (errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR), errmsg("array must be one-dimensional"))); -- 2.11.0