Merge epotemkin@bk-internal.mysql.com:/home/bk/mysql-5.0-opt

into  moonbone.local:/work/19862-bug-5.0-opt-mysql


sql/item_func.h:
  Auto merged
sql/sql_select.cc:
  Auto merged

mysql-test/r/sp.result

@@ -5057,4 +5057,23 @@ concat('data was: /', var1, '/')
 data was: /1/
 drop table t3|
 drop procedure bug15217|
+drop procedure if exists bug19862|
+CREATE TABLE t11 (a INT)|
+CREATE TABLE t12 (a INT)|
+CREATE FUNCTION bug19862(x INT) RETURNS INT
+BEGIN
+INSERT INTO t11 VALUES (x);
+RETURN x+1;
+END|
+INSERT INTO t12 VALUES (1), (2)|
+SELECT bug19862(a) FROM t12 ORDER BY 1|
+bug19862(a)
+2
+3
+SELECT * FROM t11|
+a
+1
+2
+DROP TABLE t11, t12|
+DROP FUNCTION bug19862|
 drop table t1,t2;

mysql-test/r/udf.result

@@ -93,6 +93,12 @@ NULL
 0R
 FR
 DROP TABLE bug19904;
+create table t1(f1 int);
+insert into t1 values(1),(2);
+explain select myfunc_int(f1) from t1 order by 1;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	2	Using temporary; Using filesort
+drop table t1;
 End of 5.0 tests.
 DROP FUNCTION metaphon;
 DROP FUNCTION myfunc_double;

mysql-test/t/sp.test

@@ -5962,6 +5962,24 @@ call bug15217()|
 drop table t3|
 drop procedure bug15217|
 
+#
+# BUG#19862: Sort with filesort by function evaluates function twice
+#
+--disable_warnings
+drop procedure if exists bug19862|
+--enable_warnings
+CREATE TABLE t11 (a INT)|
+CREATE TABLE t12 (a INT)|
+CREATE FUNCTION bug19862(x INT) RETURNS INT
+  BEGIN
+    INSERT INTO t11 VALUES (x);
+    RETURN x+1;
+  END|
+INSERT INTO t12 VALUES (1), (2)|
+SELECT bug19862(a) FROM t12 ORDER BY 1|
+SELECT * FROM t11|
+DROP TABLE t11, t12|
+DROP FUNCTION bug19862|
 #
 # BUG#NNNN: New bug synopsis
 #

mysql-test/t/udf.test

@@ -109,6 +109,13 @@ SELECT myfunc_double(n) AS f FROM bug19904;
 SELECT metaphon(v) AS f FROM bug19904;
 DROP TABLE bug19904;
 
+#
+# Bug#19862: Sort with filesort by function evaluates function twice
+#
+create table t1(f1 int);
+insert into t1 values(1),(2);
+explain select myfunc_int(f1) from t1 order by 1;
+drop table t1;
 --echo End of 5.0 tests.
 
 #

sql/item.h

@@ -752,6 +752,7 @@ class Item {
   virtual bool find_item_in_field_list_processor(byte *arg) { return 0; }
   virtual bool change_context_processor(byte *context) { return 0; }
   virtual bool reset_query_id_processor(byte *query_id) { return 0; }
+  virtual bool func_type_checker_processor(byte *arg) { return 0; }
 
   virtual Item *equal_fields_propagator(byte * arg) { return this; }
   virtual Item *set_no_const_sub(byte *arg) { return this; }

sql/item_func.cc

@@ -398,6 +398,13 @@ Field *Item_func::tmp_table_field(TABLE *t_arg)
   return res;
 }
 
+
+bool Item_func::func_type_checker_processor(byte *arg)
+{
+  return *((Functype*)arg) == functype();
+}
+
+
 my_decimal *Item_func::val_decimal(my_decimal *decimal_value)
 {
   DBUG_ASSERT(fixed);

sql/item_func.h

@@ -55,7 +55,7 @@ class Item_func :public Item_result_field
                   NOT_FUNC, NOT_ALL_FUNC,
                   NOW_FUNC, TRIG_COND_FUNC,
                   GUSERVAR_FUNC, COLLATE_FUNC,
-                  EXTRACT_FUNC, CHAR_TYPECAST_FUNC, FUNC_SP };
+                  EXTRACT_FUNC, CHAR_TYPECAST_FUNC, FUNC_SP, UDF_FUNC };
   enum optimize_type { OPTIMIZE_NONE,OPTIMIZE_KEY,OPTIMIZE_OP, OPTIMIZE_NULL,
                        OPTIMIZE_EQUAL };
   enum Type type() const { return FUNC_ITEM; }
@@ -189,6 +189,7 @@ class Item_func :public Item_result_field
   Item *transform(Item_transformer transformer, byte *arg);
   void traverse_cond(Cond_traverser traverser,
                      void * arg, traverse_order order);
+  bool func_type_checker_processor(byte *arg);
 };
 
 
@@ -933,6 +934,7 @@ class Item_udf_func :public Item_func
   Item_udf_func(udf_func *udf_arg, List<Item> &list)
     :Item_func(list), udf(udf_arg) {}
   const char *func_name() const { return udf.name(); }
+  enum Functype functype() const   { return UDF_FUNC; }
   bool fix_fields(THD *thd, Item **ref)
   {
     DBUG_ASSERT(fixed == 0);

sql/sql_select.cc

@@ -1064,6 +1064,26 @@ JOIN::optimize()
     {
       need_tmp=1; simple_order=simple_group=0;	// Force tmp table without sort
     }
+    if (order)
+    {
+      /*
+        Force using of tmp table if sorting by a SP or UDF function due to
+        their expensive and probably non-deterministic nature.
+      */
+      for (ORDER *tmp_order= order; tmp_order ; tmp_order=tmp_order->next)
+      {
+        Item *item= *tmp_order->item;
+        Item_func::Functype type=Item_func::FUNC_SP;
+        Item_func::Functype type1=Item_func::UDF_FUNC;
+        if (item->walk(&Item::func_type_checker_processor,(byte*)&type) ||
+            item->walk(&Item::func_type_checker_processor,(byte*)&type1))
+        {
+          /* Force tmp table without sort */
+          need_tmp=1; simple_order=simple_group=0;
+          break;
+        }
+      }
+    }
   }
 
   tmp_having= having;