Improve plpgsql's ability to report tuple incompatibility problems.

Volkan YAZICI

diff --git a/src/pl/plpgsql/src/pl_exec.c b/src/pl/plpgsql/src/pl_exec.c
index b98fde4..afc7963 100644 (file)
--- a/src/pl/plpgsql/src/pl_exec.c
+++ b/src/pl/plpgsql/src/pl_exec.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *       $PostgreSQL: pgsql/src/pl/plpgsql/src/pl_exec.c,v 1.219 2008/09/01 22:30:33 tgl Exp $
+ *       $PostgreSQL: pgsql/src/pl/plpgsql/src/pl_exec.c,v 1.220 2008/09/09 15:14:08 alvherre Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -188,7 +188,8 @@ static Datum exec_simple_cast_value(Datum value, Oid valtype,
                                           Oid reqtype, int32 reqtypmod,
                                           bool isnull);
 static void exec_init_tuple_store(PLpgSQL_execstate *estate);
-static bool compatible_tupdesc(TupleDesc td1, TupleDesc td2);
+static void validate_tupdesc_compat(TupleDesc expected, TupleDesc returned,
+                                               const char *msg);
 static void exec_set_found(PLpgSQL_execstate *estate, bool state);
 static void plpgsql_create_econtext(PLpgSQL_execstate *estate);
 static void free_var(PLpgSQL_var *var);
@@ -384,11 +385,9 @@ plpgsql_exec_function(PLpgSQL_function *func, FunctionCallInfo fcinfo)
                        {
                                case TYPEFUNC_COMPOSITE:
                                        /* got the expected result rowtype, now check it */
-                                       if (estate.rettupdesc == NULL ||
-                                               !compatible_tupdesc(estate.rettupdesc, tupdesc))
-                                               ereport(ERROR,
-                                                               (errcode(ERRCODE_DATATYPE_MISMATCH),
-                                                                errmsg("returned record type does not match expected record type")));
+                                       validate_tupdesc_compat(tupdesc, estate.rettupdesc,
+                                                                                       gettext_noop("returned record type does "
+                                                                                                                "not match expected record type"));
                                        break;
                                case TYPEFUNC_RECORD:
 
@@ -705,11 +704,10 @@ plpgsql_exec_trigger(PLpgSQL_function *func,
                rettup = NULL;
        else
        {
-               if (!compatible_tupdesc(estate.rettupdesc,
-                                                               trigdata->tg_relation->rd_att))
-                       ereport(ERROR,
-                                       (errcode(ERRCODE_DATATYPE_MISMATCH),
-                                        errmsg("returned tuple structure does not match table of trigger event")));
+               validate_tupdesc_compat(trigdata->tg_relation->rd_att,
+                                                               estate.rettupdesc,
+                                                               gettext_noop("returned tuple structure does "
+                                                                                        "not match table of trigger event"));
                /* Copy tuple to upper executor memory */
                rettup = SPI_copytuple((HeapTuple) DatumGetPointer(estate.retval));
        }
@@ -2199,11 +2197,11 @@ exec_stmt_return_next(PLpgSQL_execstate *estate,
                                                  (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
                                                   errmsg("record \"%s\" is not assigned yet",
                                                                  rec->refname),
-                                                  errdetail("The tuple structure of a not-yet-assigned record is indeterminate.")));
-                                       if (!compatible_tupdesc(tupdesc, rec->tupdesc))
-                                               ereport(ERROR,
-                                                               (errcode(ERRCODE_DATATYPE_MISMATCH),
-                                               errmsg("wrong record type supplied in RETURN NEXT")));
+                                                  errdetail("The tuple structure of a not-yet-assigned"
+                                                                        " record is indeterminate.")));
+                                       validate_tupdesc_compat(tupdesc, rec->tupdesc,
+                                                                   gettext_noop("wrong record type supplied "
+                                                                                                                "in RETURN NEXT"));
                                        tuple = rec->tup;
                                }
                                break;
@@ -2309,10 +2307,9 @@ exec_stmt_return_query(PLpgSQL_execstate *estate,
                                                                                   stmt->params);
        }
 
-       if (!compatible_tupdesc(estate->rettupdesc, portal->tupDesc))
-               ereport(ERROR,
-                               (errcode(ERRCODE_DATATYPE_MISMATCH),
-                 errmsg("structure of query does not match function result type")));
+       validate_tupdesc_compat(estate->rettupdesc, portal->tupDesc,
+                                                       gettext_noop("structure of query does not match "
+                                                                                "function result type"));
 
        while (true)
        {
@@ -5145,23 +5142,42 @@ exec_simple_check_plan(PLpgSQL_expr *expr)
 }
 
 /*
- * Check two tupledescs have matching number and types of attributes
+ * Validates compatibility of supplied TupleDesc pair by checking number and type
+ * of attributes.
  */
-static bool
-compatible_tupdesc(TupleDesc td1, TupleDesc td2)
+static void
+validate_tupdesc_compat(TupleDesc expected, TupleDesc returned, const char *msg)
 {
-       int                     i;
+       int                i;
+       const char dropped_column_type[] = gettext_noop("n/a (dropped column)");
 
-       if (td1->natts != td2->natts)
-               return false;
+       if (!expected || !returned)
+               ereport(ERROR,
+                               (errcode(ERRCODE_DATATYPE_MISMATCH),
+                                errmsg("%s", _(msg))));
 
-       for (i = 0; i < td1->natts; i++)
-       {
-               if (td1->attrs[i]->atttypid != td2->attrs[i]->atttypid)
-                       return false;
-       }
+       if (expected->natts != returned->natts)
+               ereport(ERROR,
+                               (errcode(ERRCODE_DATATYPE_MISMATCH),
+                                errmsg("%s", _(msg)),
+                                errdetail("Number of returned columns (%d) does not match "
+                                                  "expected column count (%d).",
+                                                  returned->natts, expected->natts)));
 
-       return true;
+       for (i = 0; i < expected->natts; i++)
+               if (expected->attrs[i]->atttypid != returned->attrs[i]->atttypid)
+                       ereport(ERROR,
+                                       (errcode(ERRCODE_DATATYPE_MISMATCH),
+                                        errmsg("%s", _(msg)),
+                                        errdetail("Returned type %s does not match expected type "
+                                                          "%s in column %s.",
+                                                          OidIsValid(returned->attrs[i]->atttypid) ?
+                                                          format_type_be(returned->attrs[i]->atttypid) :
+                                                          _(dropped_column_type),
+                                                          OidIsValid(expected->attrs[i]->atttypid) ?
+                                                          format_type_be(expected->attrs[i]->atttypid) :
+                                                          _(dropped_column_type),
+                                                          NameStr(expected->attrs[i]->attname))));
 }
 
 /* ----------