Fix error reporting for index expressions of prohibited types.

If CheckAttributeType() threw an error about the datatype of an
index expression column, it would report an empty column name,
which is pretty unhelpful and certainly not the intended behavior.
I (tgl) evidently broke this in commit cfc5008a5, by not noticing
that the column's attname was used above where I'd placed the
assignment of it.

In HEAD and v12, this is trivially fixable by moving up the
assignment of attname.  Before v12 the code is a bit more messy;
to avoid doing substantial refactoring, I took the lazy way out
and just put in two copies of the assignment code.

Report and patch by Amit Langote.  Back-patch to all supported
branches.

Discussion: https://postgr.es/m/CA+HiwqFA+BGyBFimjiYXXMa2Hc3fcL0+OJOyzUNjhU4NCa_XXw@mail.gmail.com

diff --git a/src/backend/catalog/index.c b/src/backend/catalog/index.c
index be363ce4dc3a75c50085bf21220804eeaf074b0e..bc20d7c750bd11621ee3fda82e1093428dfb5db9 100644 (file)
--- a/src/backend/catalog/index.c
+++ b/src/backend/catalog/index.c
@@ -368,6 +368,14 @@ ConstructTupleDescriptor(Relation heapRelation,
             */
            memcpy(to, from, ATTRIBUTE_FIXED_PART_SIZE);
 
+           /*
+            * Set the attribute name as specified by caller.
+            */
+           if (colnames_item == NULL)  /* shouldn't happen */
+               elog(ERROR, "too few entries in colnames list");
+           namestrcpy(&to->attname, (const char *) lfirst(colnames_item));
+           colnames_item = lnext(colnames_item);
+
            /*
             * Fix the stuff that should not be the same as the underlying
             * attr
@@ -392,6 +400,14 @@ ConstructTupleDescriptor(Relation heapRelation,
 
            MemSet(to, 0, ATTRIBUTE_FIXED_PART_SIZE);
 
+           /*
+            * Set the attribute name as specified by caller.
+            */
+           if (colnames_item == NULL)  /* shouldn't happen */
+               elog(ERROR, "too few entries in colnames list");
+           namestrcpy(&to->attname, (const char *) lfirst(colnames_item));
+           colnames_item = lnext(colnames_item);
+
            if (indexpr_item == NULL)   /* shouldn't happen */
                elog(ERROR, "too few entries in indexprs list");
            indexkey = (Node *) lfirst(indexpr_item);
@@ -445,14 +461,6 @@ ConstructTupleDescriptor(Relation heapRelation,
         */
        to->attrelid = InvalidOid;
 
-       /*
-        * Set the attribute name as specified by caller.
-        */
-       if (colnames_item == NULL)  /* shouldn't happen */
-           elog(ERROR, "too few entries in colnames list");
-       namestrcpy(&to->attname, (const char *) lfirst(colnames_item));
-       colnames_item = lnext(colnames_item);
-
        /*
         * Check the opclass and index AM to see if either provides a keytype
         * (overriding the attribute type).  Opclass (if exists) takes

diff --git a/src/test/regress/expected/create_index.out b/src/test/regress/expected/create_index.out
index 90b671f5b91d4f15399e736aba1c41fd8173ad42..e7d7c7aee6d84c24e1d7d9117ebb2f0c22021cfa 100644 (file)
--- a/src/test/regress/expected/create_index.out
+++ b/src/test/regress/expected/create_index.out
@@ -2417,6 +2417,23 @@ ERROR:  duplicate key value violates unique constraint "func_index_index"
 DETAIL:  Key (textcat(f1, f2))=(ABCDEF) already exists.
 -- but this shouldn't:
 INSERT INTO func_index_heap VALUES('QWERTY');
+-- while we're here, see that the metadata looks sane
+\d func_index_heap
+         Table "public.func_index_heap"
+ Column | Type | Collation | Nullable | Default 
+--------+------+-----------+----------+---------
+ f1     | text |           |          | 
+ f2     | text |           |          | 
+Indexes:
+    "func_index_index" UNIQUE, btree (textcat(f1, f2))
+
+\d func_index_index
+     Index "public.func_index_index"
+ Column  | Type | Key? |   Definition    
+---------+------+------+-----------------
+ textcat | text | yes  | textcat(f1, f2)
+unique, btree, for table "public.func_index_heap"
+
 --
 -- Same test, expressional index
 --
@@ -2432,6 +2449,26 @@ ERROR:  duplicate key value violates unique constraint "func_index_index"
 DETAIL:  Key ((f1 || f2))=(ABCDEF) already exists.
 -- but this shouldn't:
 INSERT INTO func_index_heap VALUES('QWERTY');
+-- while we're here, see that the metadata looks sane
+\d func_index_heap
+         Table "public.func_index_heap"
+ Column | Type | Collation | Nullable | Default 
+--------+------+-----------+----------+---------
+ f1     | text |           |          | 
+ f2     | text |           |          | 
+Indexes:
+    "func_index_index" UNIQUE, btree ((f1 || f2))
+
+\d func_index_index
+  Index "public.func_index_index"
+ Column | Type | Key? | Definition 
+--------+------+------+------------
+ expr   | text | yes  | (f1 || f2)
+unique, btree, for table "public.func_index_heap"
+
+-- this should fail because of unsafe column type (anonymous record)
+create index on func_index_heap ((f1 || f2), (row(f1, f2)));
+ERROR:  column "row" has pseudo-type record
 --
 -- Test unique index with included columns
 --

diff --git a/src/test/regress/sql/create_index.sql b/src/test/regress/sql/create_index.sql
index 6eee92bf973ca0543dc92b0ee67202dcc9478bee..283c4e6c18e4f8933763d1400f044226ed72572d 100644 (file)
--- a/src/test/regress/sql/create_index.sql
+++ b/src/test/regress/sql/create_index.sql
@@ -725,6 +725,10 @@ INSERT INTO func_index_heap VALUES('ABCD', 'EF');
 -- but this shouldn't:
 INSERT INTO func_index_heap VALUES('QWERTY');
 
+-- while we're here, see that the metadata looks sane
+\d func_index_heap
+\d func_index_index
+
 
 --
 -- Same test, expressional index
@@ -741,6 +745,14 @@ INSERT INTO func_index_heap VALUES('ABCD', 'EF');
 -- but this shouldn't:
 INSERT INTO func_index_heap VALUES('QWERTY');
 
+-- while we're here, see that the metadata looks sane
+\d func_index_heap
+\d func_index_index
+
+-- this should fail because of unsafe column type (anonymous record)
+create index on func_index_heap ((f1 || f2), (row(f1, f2)));
+
+
 --
 -- Test unique index with included columns
 --