Merge moonlight.intranet:/home/tomash/src/mysql_ab/mysql-5.0

into  moonlight.intranet:/home/tomash/src/mysql_ab/mysql-5.0-bug21081

mysql-test/r/trigger.result

@@ -1173,4 +1173,16 @@ TRIGGER t2_bi BEFORE INSERT ON t2 FOR EACH ROW SET @a = 2;
 ERROR HY000: String '1234567890abcdefghij1234567890abcdefghij1234567890abcdefghijQWERTY' is too long for host name (should be no longer than 60)
 DROP TABLE t1;
 DROP TABLE t2;
+drop table if exists t1;
+create table t1 (i int, j int key);
+insert into t1 values (1,1), (2,2), (3,3);
+create trigger t1_bu before update on t1 for each row
+set new.j = new.j + 10;
+update t1 set i= i+ 10 where j > 2;
+select * from t1;
+i	j
+1	1
+2	2
+13	13
+drop table t1;
 End of 5.0 tests

mysql-test/t/trigger.test

@@ -1421,4 +1421,23 @@ DROP TABLE t1;
 DROP TABLE t2;
 
 
+#
+# Bug#20670 "UPDATE using key and invoking trigger that modifies
+#            this key does not stop"
+#
+
+--disable_warnings
+drop table if exists t1;
+--enable_warnings
+create table t1 (i int, j int key);
+insert into t1 values (1,1), (2,2), (3,3);
+create trigger t1_bu before update on t1 for each row
+  set new.j = new.j + 10;
+# This should not work indefinitely and should cause
+# expected result
+update t1 set i= i+ 10 where j > 2;
+select * from t1;
+drop table t1;
+
+
 --echo End of 5.0 tests

sql/key.cc

@@ -18,6 +18,7 @@
 /* Functions to handle keys and fields in forms */
 
 #include "mysql_priv.h"
+#include "sql_trigger.h"
 
 	/*
 	** Search after with key field is. If no key starts with field test
@@ -342,12 +343,24 @@ void key_unpack(String *to,TABLE *table,uint idx)
 
 
 /*
-  Return 1 if any field in a list is part of key or the key uses a field
-  that is automaticly updated (like a timestamp)
+  Check if key uses field that is listed in passed field list or is
+  automatically updated (like a timestamp) or can be updated by before
+  update trigger defined on the table.
+
+  SYNOPSIS
+    is_key_used()
+      table   TABLE object with which keys and fields are associated.
+      idx     Key to be checked.
+      fields  List of fields to be checked.
+
+  RETURN VALUE
+    TRUE   Key uses field which meets one the above conditions
+    FALSE  Otherwise
 */
 
-bool check_if_key_used(TABLE *table, uint idx, List<Item> &fields)
+bool is_key_used(TABLE *table, uint idx, List<Item> &fields)
 {
+  Table_triggers_list *triggers= table->triggers;
   List_iterator_fast<Item> f(fields);
   KEY_PART_INFO *key_part,*key_part_end;
   for (key_part=table->key_info[idx].key_part,key_part_end=key_part+
@@ -366,6 +379,9 @@ bool check_if_key_used(TABLE *table, uint idx, List<Item> &fields)
       if (key_part->field->eq(field->field))
 	return 1;
     }
+    if (triggers &&
+        triggers->is_updated_in_before_update_triggers(key_part->field))
+      return 1;
   }
 
   /*
@@ -374,7 +390,7 @@ bool check_if_key_used(TABLE *table, uint idx, List<Item> &fields)
   */
   if (idx != table->s->primary_key && table->s->primary_key < MAX_KEY &&
       (table->file->table_flags() & HA_PRIMARY_KEY_IN_READ_INDEX))
-    return check_if_key_used(table, table->s->primary_key, fields);
+    return is_key_used(table, table->s->primary_key, fields);
   return 0;
 }
 

sql/mysql_priv.h

@@ -1113,7 +1113,7 @@ void key_restore(byte *to_record, byte *from_key, KEY *key_info,
                  uint key_length);
 bool key_cmp_if_same(TABLE *form,const byte *key,uint index,uint key_length);
 void key_unpack(String *to,TABLE *form,uint index);
-bool check_if_key_used(TABLE *table, uint idx, List<Item> &fields);
+bool is_key_used(TABLE *table, uint idx, List<Item> &fields);
 int key_cmp(KEY_PART_INFO *key_part, const byte *key, uint key_length);
 
 bool init_errmessage(void);

sql/opt_range.cc

@@ -6127,42 +6127,42 @@ static bool null_part_in_key(KEY_PART *key_part, const char *key, uint length)
 }
 
 
-bool QUICK_SELECT_I::check_if_keys_used(List<Item> *fields)
+bool QUICK_SELECT_I::is_keys_used(List<Item> *fields)
 {
-  return check_if_key_used(head, index, *fields);
+  return is_key_used(head, index, *fields);
 }
 
-bool QUICK_INDEX_MERGE_SELECT::check_if_keys_used(List<Item> *fields)
+bool QUICK_INDEX_MERGE_SELECT::is_keys_used(List<Item> *fields)
 {
   QUICK_RANGE_SELECT *quick;
   List_iterator_fast<QUICK_RANGE_SELECT> it(quick_selects);
   while ((quick= it++))
   {
-    if (check_if_key_used(head, quick->index, *fields))
+    if (is_key_used(head, quick->index, *fields))
       return 1;
   }
   return 0;
 }
 
-bool QUICK_ROR_INTERSECT_SELECT::check_if_keys_used(List<Item> *fields)
+bool QUICK_ROR_INTERSECT_SELECT::is_keys_used(List<Item> *fields)
 {
   QUICK_RANGE_SELECT *quick;
   List_iterator_fast<QUICK_RANGE_SELECT> it(quick_selects);
   while ((quick= it++))
   {
-    if (check_if_key_used(head, quick->index, *fields))
+    if (is_key_used(head, quick->index, *fields))
       return 1;
   }
   return 0;
 }
 
-bool QUICK_ROR_UNION_SELECT::check_if_keys_used(List<Item> *fields)
+bool QUICK_ROR_UNION_SELECT::is_keys_used(List<Item> *fields)
 {
   QUICK_SELECT_I *quick;
   List_iterator_fast<QUICK_SELECT_I> it(quick_selects);
   while ((quick= it++))
   {
-    if (quick->check_if_keys_used(fields))
+    if (quick->is_keys_used(fields))
       return 1;
   }
   return 0;

sql/opt_range.h

@@ -225,8 +225,9 @@ public:
     Return 1 if any index used by this quick select
      a) uses field that is listed in passed field list or
      b) is automatically updated (like a timestamp)
+     c) can be updated by one of before update triggers defined on table
   */
-  virtual bool check_if_keys_used(List<Item> *fields);
+  virtual bool is_keys_used(List<Item> *fields);
 
   /*
     rowid of last row retrieved by this quick select. This is used only when
@@ -423,7 +424,7 @@ public:
   int get_type() { return QS_TYPE_INDEX_MERGE; }
   void add_keys_and_lengths(String *key_names, String *used_lengths);
   void add_info_string(String *str);
-  bool check_if_keys_used(List<Item> *fields);
+  bool is_keys_used(List<Item> *fields);
 #ifndef DBUG_OFF
   void dbug_dump(int indent, bool verbose);
 #endif
@@ -482,7 +483,7 @@ public:
   int get_type() { return QS_TYPE_ROR_INTERSECT; }
   void add_keys_and_lengths(String *key_names, String *used_lengths);
   void add_info_string(String *str);
-  bool check_if_keys_used(List<Item> *fields);
+  bool is_keys_used(List<Item> *fields);
 #ifndef DBUG_OFF
   void dbug_dump(int indent, bool verbose);
 #endif
@@ -536,7 +537,7 @@ public:
   int get_type() { return QS_TYPE_ROR_UNION; }
   void add_keys_and_lengths(String *key_names, String *used_lengths);
   void add_info_string(String *str);
-  bool check_if_keys_used(List<Item> *fields);
+  bool is_keys_used(List<Item> *fields);
 #ifndef DBUG_OFF
   void dbug_dump(int indent, bool verbose);
 #endif

sql/sql_trigger.cc

@@ -1547,6 +1547,38 @@ void Table_triggers_list::mark_fields_used(THD *thd, trg_event_type event)
 }
 
 
+/*
+  Check if field of subject table can be changed in before update trigger.
+
+  SYNOPSIS
+    is_updated_in_before_update_triggers()
+      field  Field object for field to be checked
+
+  NOTE
+    Field passed to this function should be bound to the same
+    TABLE object as Table_triggers_list.
+
+  RETURN VALUE
+    TRUE   Field is changed
+    FALSE  Otherwise
+*/
+
+bool Table_triggers_list::is_updated_in_before_update_triggers(Field *fld)
+{
+  Item_trigger_field *trg_fld;
+  for (trg_fld= trigger_fields[TRG_EVENT_UPDATE][TRG_ACTION_BEFORE];
+       trg_fld != 0;
+       trg_fld= trg_fld->next_trg_field)
+  {
+    if (trg_fld->get_settable_routine_parameter() &&
+        trg_fld->field_idx != (uint)-1 &&
+        table->field[trg_fld->field_idx]->eq(fld))
+      return TRUE;
+  }
+  return FALSE;
+}
+
+
 /*
   Trigger BUG#14090 compatibility hook
 

sql/sql_trigger.h

@@ -116,15 +116,12 @@ public:
             bodies[TRG_EVENT_DELETE][TRG_ACTION_AFTER]);
   }
 
-  bool has_before_update_triggers()
-  {
-    return test(bodies[TRG_EVENT_UPDATE][TRG_ACTION_BEFORE]);
-  }
-
   void set_table(TABLE *new_table);
 
   void mark_fields_used(THD *thd, trg_event_type event);
 
+  bool is_updated_in_before_update_triggers(Field *fld);
+
   friend class Item_trigger_field;
   friend int sp_cache_routines_and_add_tables_for_triggers(THD *thd, LEX *lex,
                                                             TABLE_LIST *table);

sql/sql_update.cc

@@ -274,7 +274,7 @@ int mysql_update(THD *thd,
   {
     used_index= select->quick->index;
     used_key_is_modified= (!select->quick->unique_key_range() &&
-                          select->quick->check_if_keys_used(&fields));
+                          select->quick->is_keys_used(&fields));
   }
   else
   {
@@ -282,7 +282,7 @@ int mysql_update(THD *thd,
     if (used_index == MAX_KEY)                  // no index for sort order
       used_index= table->file->key_used_on_scan;
     if (used_index != MAX_KEY)
-      used_key_is_modified= check_if_key_used(table, used_index, fields);
+      used_key_is_modified= is_key_used(table, used_index, fields);
   }
 
   if (used_key_is_modified || order)
@@ -1189,21 +1189,15 @@ static bool safe_update_on_fly(JOIN_TAB *join_tab, List<Item> *fields)
     return TRUE;				// At most one matching row
   case JT_REF:
   case JT_REF_OR_NULL:
-    return !check_if_key_used(table, join_tab->ref.key, *fields) &&
-           !(table->triggers &&
-             table->triggers->has_before_update_triggers());
+    return !is_key_used(table, join_tab->ref.key, *fields);
   case JT_ALL:
     /* If range search on index */
     if (join_tab->quick)
-      return !join_tab->quick->check_if_keys_used(fields) &&
-             !(table->triggers &&
-               table->triggers->has_before_update_triggers());
+      return !join_tab->quick->is_keys_used(fields);
     /* If scanning in clustered key */
     if ((table->file->table_flags() & HA_PRIMARY_KEY_IN_READ_INDEX) &&
 	table->s->primary_key < MAX_KEY)
-      return !check_if_key_used(table, table->s->primary_key, *fields) &&
-             !(table->triggers &&
-               table->triggers->has_before_update_triggers());
+      return !is_key_used(table, table->s->primary_key, *fields);
     return TRUE;
   default:
     break;					// Avoid compler warning