Bug#21625929: ASSERTION FAILED: FALSE IN CREATE_TMP_FIELD

WITH UNKNOWN OUTER FIELD

Some assertions in sql_tmp_table.cc were added in a merge
from 5.6. They ruled out the possibility that a temporary
table column could be created on the basis of a prepared
statement parameter.

Fixed by reverting the behavior back to 5.6 in this
particular case: I.e. not creating columns for parameters
during PREPARE. During EXECUTE we don't have this problem,
obviously, since at that time the parameters have been
substituted by constant expressions.

Author: Martin Hansson

mysql-test/r/sp.result

@@ -7858,3 +7858,14 @@ PREPARE s FROM
 ERROR 42000: Expression #1 of SELECT list is not in GROUP BY clause and contains nonaggregated column 'test.t1.b' which is not functionally dependent on columns in GROUP BY clause; this is incompatible with sql_mode=only_full_group_by
 DROP TABLE t1, t2;
 SET sql_mode = DEFAULT;
+#
+# ASSERTION FAILED: FALSE IN CREATE_TMP_FIELD WITH UNKNOWN OUTER FIELD
+#
+CREATE TABLE t1 ( a INT );
+SET @v = 1;
+PREPARE stmt FROM 'SELECT 1 FROM ( SELECT ? FROM t1 GROUP BY a ) al;';
+EXECUTE stmt USING @v;
+1
+PREPARE stmt FROM 'CREATE TABLE t2 AS SELECT ? FROM t1';
+EXECUTE stmt USING @v;
+DROP TABLE t1, t2;

mysql-test/t/sp.test

@@ -9096,3 +9096,18 @@ PREPARE s FROM
 
 DROP TABLE t1, t2;
 SET sql_mode = DEFAULT;
+
+--echo #
+--echo # ASSERTION FAILED: FALSE IN CREATE_TMP_FIELD WITH UNKNOWN OUTER FIELD
+--echo #
+CREATE TABLE t1 ( a INT );
+
+SET @v = 1;
+
+PREPARE stmt FROM 'SELECT 1 FROM ( SELECT ? FROM t1 GROUP BY a ) al;';
+EXECUTE stmt USING @v;
+
+PREPARE stmt FROM 'CREATE TABLE t2 AS SELECT ? FROM t1';
+EXECUTE stmt USING @v;
+
+DROP TABLE t1, t2;

sql/sql_tmp_table.cc

@@ -242,10 +242,10 @@ static Field *create_tmp_field_for_schema(THD *thd, Item *item, TABLE *table)
                        If modify_item is 0 then fill_record() will update
                        the temporary table
 
-  @retval
-    NULL		on error
-  @retval
-    new_created field
+  @retval NULL On error. This also happens if the item is a prepared statement
+  parameter.
+
+  @retval new_created field
 */
 
 Field *create_tmp_field(THD *thd, TABLE *table,Item *item, Item::Type type,
@@ -390,6 +390,8 @@ Field *create_tmp_field(THD *thd, TABLE *table,Item *item, Item::Type type,
       break;
     result->set_derivation(item->collation.derivation);
     break;
+  case Item::PARAM_ITEM:
+    return NULL;
   default:					// Dosen't have to be stored
     DBUG_ASSERT(false);
     break;
@@ -954,6 +956,8 @@ create_tmp_table(THD *thd, Temp_table_param *param, List<Item> &fields,
 
       if (!new_field)
       {
+        if (type == Item::PARAM_ITEM)
+          goto update_hidden;
         DBUG_ASSERT(thd->is_fatal_error);
         goto err;				// Got OOM
       }