Merge of changes from the main tree to tree for WL#1218 "Triggers".

include/mysqld_error.h

@@ -374,4 +374,9 @@
 #define ER_VIEW_INVALID 1355
 #define ER_SP_NO_DROP_SP 1356
 #define ER_SP_GOTO_IN_HNDLR 1357
-#define ER_ERROR_MESSAGES 358
+#define ER_TRG_ALREADY_EXISTS 1358
+#define ER_TRG_DOES_NOT_EXIST 1359
+#define ER_TRG_ON_VIEW_OR_TEMP_TABLE 1360
+#define ER_TRG_CANT_CHANGE_ROW 1361
+#define ER_TRG_NO_SUCH_ROW_IN_TRG 1362
+#define ER_ERROR_MESSAGES 363

mysql-test/r/trigger.result

+drop table if exists t1, t2;
+drop view if exists v1;
+create table t1 (i int);
+create trigger trg before insert on t1 for each row set @a:=1;
+set @a:=0;
+select @a;
+@a
+0
+insert into t1 values (1);
+select @a;
+@a
+1
+drop trigger t1.trg;
+create trigger trg before insert on t1 for each row set @a:=new.i;
+insert into t1 values (123);
+select @a;
+@a
+123
+drop trigger t1.trg;
+drop table t1;
+create table t1 (i int not null, j int);
+create trigger trg before insert on t1 for each row 
+begin 
+if isnull(new.j) then
+set new.j:= new.i * 10;
+end if;
+end|
+insert into t1 (i) values (1)|
+insert into t1 (i,j) values (2, 3)|
+select * from t1|
+i	j
+1	10
+2	3
+drop trigger t1.trg|
+drop table t1|
+create table t1 (i int not null primary key);
+create trigger trg after insert on t1 for each row 
+set @a:= if(@a,concat(@a, ":", new.i), new.i);
+set @a:="";
+insert into t1 values (2),(3),(4),(5);
+select @a;
+@a
+2:3:4:5
+drop trigger t1.trg;
+drop table t1;
+create table t1 (aid int not null primary key, balance int not null default 0);
+insert into t1 values (1, 1000), (2,3000);
+create trigger trg before update on t1 for each row 
+begin
+declare loc_err varchar(255);
+if abs(new.balance - old.balance) > 1000 then
+set new.balance:= old.balance;
+set loc_err := concat("Too big change for aid = ", new.aid);
+set @update_failed:= if(@update_failed, concat(@a, ":", loc_err), loc_err);
+end if;
+end|
+set @update_failed:=""|
+update t1 set balance=1500|
+select @update_failed;
+select * from t1|
+@update_failed
+Too big change for aid = 2
+aid	balance
+1	1500
+2	3000
+drop trigger t1.trg|
+drop table t1|
+create table t1 (i int);
+insert into t1 values (1),(2),(3),(4);
+create trigger trg after update on t1 for each row 
+set @total_change:=@total_change + new.i - old.i;
+set @total_change:=0;
+update t1 set i=3;
+select @total_change;
+@total_change
+2
+drop trigger t1.trg;
+drop table t1;
+create table t1 (i int);
+insert into t1 values (1),(2),(3),(4);
+create trigger trg before delete on t1 for each row 
+set @del_sum:= @del_sum + old.i;
+set @del_sum:= 0;
+delete from t1 where i <= 3;
+select @del_sum;
+@del_sum
+6
+drop trigger t1.trg;
+drop table t1;
+create table t1 (i int);
+insert into t1 values (1),(2),(3),(4);
+create trigger trg after delete on t1 for each row set @del:= 1;
+set @del:= 0;
+delete from t1 where i <> 0;
+select @del;
+@del
+1
+drop trigger t1.trg;
+drop table t1;
+create table t1 (i int, j int);
+create trigger trg1 before insert on t1 for each row 
+begin
+if new.j > 10 then
+set new.j := 10;
+end if;
+end|
+create trigger trg2 before update on t1 for each row 
+begin
+if old.i % 2 = 0 then
+set new.j := -1;
+end if;
+end|
+create trigger trg3 after update on t1 for each row 
+begin
+if new.j = -1 then
+set @fired:= "Yes";
+end if;
+end|
+set @fired:="";
+insert into t1 values (1,2),(2,3),(3,14);
+select @fired;
+@fired
+
+select * from t1;
+i	j
+1	2
+2	3
+3	10
+update t1 set j= 20;
+select @fired;
+@fired
+Yes
+select * from t1;
+i	j
+1	20
+2	-1
+3	20
+drop trigger t1.trg1;
+drop trigger t1.trg2;
+drop trigger t1.trg3;
+drop table t1;
+create table t1 (i int);
+create trigger trg before insert on t1 for each row set @a:= old.i;
+ERROR HY000: There is no OLD row in on INSERT trigger
+create trigger trg before delete on t1 for each row set @a:= new.i;
+ERROR HY000: There is no NEW row in on DELETE trigger
+create trigger trg before update on t1 for each row set old.i:=1;
+ERROR HY000: Updating of OLD row is not allowed in trigger
+create trigger trg before delete on t1 for each row set new.i:=1;
+ERROR HY000: There is no NEW row in on DELETE trigger
+create trigger trg after update on t1 for each row set new.i:=1;
+ERROR HY000: Updating of NEW row is not allowed in after trigger
+create trigger trg before insert on t2 for each row set @a:=1;
+ERROR 42S02: Table 'test.t2' doesn't exist
+create trigger trg before insert on t1 for each row set @a:=1;
+create trigger trg after insert on t1 for each row set @a:=1;
+ERROR HY000: Trigger already exists
+create trigger trg2 before insert on t1 for each row set @a:=1;
+ERROR HY000: Trigger already exists
+drop trigger t1.trg;
+drop trigger t1.trg;
+ERROR HY000: Trigger does not exist
+create view v1 as select * from t1;
+create trigger trg before insert on v1 for each row set @a:=1;
+ERROR HY000: Trigger's 'v1' is view or temporary table
+drop view v1;
+drop table t1;
+create temporary table t1 (i int);
+create trigger trg before insert on t1 for each row set @a:=1;
+ERROR HY000: Trigger's 't1' is view or temporary table
+drop table t1;

mysql-test/t/trigger.test

+#
+# Basic triggers test
+#
+
+--disable_warnings
+drop table if exists t1, t2;
+drop view if exists v1;
+--enable_warnings
+
+create table t1 (i int);
+
+# let us test some very simple trigger
+create trigger trg before insert on t1 for each row set @a:=1;
+set @a:=0;
+select @a;
+insert into t1 values (1);
+select @a;
+drop trigger t1.trg;
+
+# let us test simple trigger reading some values 
+create trigger trg before insert on t1 for each row set @a:=new.i;
+insert into t1 values (123);
+select @a;
+drop trigger t1.trg;
+
+drop table t1;
+
+# Let us test before insert trigger
+# Such triggers can be used for setting complex default values
+create table t1 (i int not null, j int);
+delimiter |;
+create trigger trg before insert on t1 for each row 
+begin 
+  if isnull(new.j) then
+    set new.j:= new.i * 10;
+  end if;
+end|
+insert into t1 (i) values (1)|
+insert into t1 (i,j) values (2, 3)|
+select * from t1|
+drop trigger t1.trg|
+drop table t1|
+delimiter ;|
+
+# After insert trigger
+# Useful for aggregating data
+create table t1 (i int not null primary key);
+create trigger trg after insert on t1 for each row 
+  set @a:= if(@a,concat(@a, ":", new.i), new.i);
+set @a:="";
+insert into t1 values (2),(3),(4),(5);
+select @a;
+drop trigger t1.trg;
+drop table t1;
+
+# Before update trigger
+# (In future we will achieve this via proper error handling in triggers)
+create table t1 (aid int not null primary key, balance int not null default 0);
+insert into t1 values (1, 1000), (2,3000);
+delimiter |;
+create trigger trg before update on t1 for each row 
+begin
+  declare loc_err varchar(255);
+  if abs(new.balance - old.balance) > 1000 then
+    set new.balance:= old.balance;
+    set loc_err := concat("Too big change for aid = ", new.aid);
+    set @update_failed:= if(@update_failed, concat(@a, ":", loc_err), loc_err);
+  end if;
+end|
+set @update_failed:=""|
+update t1 set balance=1500|
+select @update_failed;
+select * from t1|
+drop trigger t1.trg|
+drop table t1|
+delimiter ;|
+
+# After update trigger
+create table t1 (i int);
+insert into t1 values (1),(2),(3),(4);
+create trigger trg after update on t1 for each row 
+  set @total_change:=@total_change + new.i - old.i;
+set @total_change:=0;
+update t1 set i=3;
+select @total_change;
+drop trigger t1.trg;
+drop table t1;
+
+# Before delete trigger
+# This can be used for aggregation too :)
+create table t1 (i int);
+insert into t1 values (1),(2),(3),(4);
+create trigger trg before delete on t1 for each row 
+  set @del_sum:= @del_sum + old.i;
+set @del_sum:= 0;
+delete from t1 where i <= 3;
+select @del_sum;
+drop trigger t1.trg;
+drop table t1;
+
+# After delete trigger. 
+# Just run out of imagination.
+create table t1 (i int);
+insert into t1 values (1),(2),(3),(4);
+create trigger trg after delete on t1 for each row set @del:= 1;
+set @del:= 0;
+delete from t1 where i <> 0;
+select @del;
+drop trigger t1.trg;
+drop table t1;
+
+# Several triggers on one table
+create table t1 (i int, j int);
+
+delimiter |;
+create trigger trg1 before insert on t1 for each row 
+begin
+  if new.j > 10 then
+    set new.j := 10;
+  end if;
+end|
+create trigger trg2 before update on t1 for each row 
+begin
+  if old.i % 2 = 0 then
+    set new.j := -1;
+  end if;
+end|
+create trigger trg3 after update on t1 for each row 
+begin
+  if new.j = -1 then
+    set @fired:= "Yes";
+  end if;
+end|
+delimiter ;|
+set @fired:="";
+insert into t1 values (1,2),(2,3),(3,14);
+select @fired;
+select * from t1;
+update t1 set j= 20;
+select @fired;
+select * from t1;
+
+drop trigger t1.trg1;
+drop trigger t1.trg2;
+drop trigger t1.trg3;
+drop table t1;
+
+
+#
+# Test of wrong column specifiers in triggers
+#
+create table t1 (i int);
+
+--error 1358
+create trigger trg before insert on t1 for each row set @a:= old.i;
+--error 1358
+create trigger trg before delete on t1 for each row set @a:= new.i;
+--error 1357
+create trigger trg before update on t1 for each row set old.i:=1;
+--error 1358
+create trigger trg before delete on t1 for each row set new.i:=1;
+--error 1357
+create trigger trg after update on t1 for each row set new.i:=1;
+# TODO: We should also test wrong field names here, we don't do it now
+#       because proper error handling is not in place yet.
+
+
+#
+# Let us test various trigger creation errors
+#
+#
+--error 1146
+create trigger trg before insert on t2 for each row set @a:=1;
+
+create trigger trg before insert on t1 for each row set @a:=1;
+--error 1354
+create trigger trg after insert on t1 for each row set @a:=1;
+--error 1354
+create trigger trg2 before insert on t1 for each row set @a:=1;
+drop trigger t1.trg;
+
+--error 1355
+drop trigger t1.trg;
+
+create view v1 as select * from t1;
+--error 1356
+create trigger trg before insert on v1 for each row set @a:=1;
+drop view v1;
+
+drop table t1;
+
+create temporary table t1 (i int);
+--error 1356
+create trigger trg before insert on t1 for each row set @a:=1;
+drop table t1;

sql/Makefile.am

@@ -61,7 +61,7 @@ noinst_HEADERS =	item.h item_func.h item_sum.h item_cmpfunc.h \
 			spatial.h gstream.h client_settings.h tzfile.h \
                         tztime.h examples/ha_example.h examples/ha_archive.h \
 			sp_head.h sp_pcontext.h sp_rcontext.h sp.h sp_cache.h \
-			parse_file.h sql_view.h
+			parse_file.h sql_view.h sql_trigger.h
 mysqld_SOURCES =	sql_lex.cc sql_handler.cc \
 			item.cc item_sum.cc item_buff.cc item_func.cc \
 			item_cmpfunc.cc item_strfunc.cc item_timefunc.cc \
@@ -95,7 +95,7 @@ mysqld_SOURCES =	sql_lex.cc sql_handler.cc \
 			tztime.cc my_time.c \
 			examples/ha_example.cc examples/ha_archive.cc \
 			sp_head.cc sp_pcontext.cc  sp_rcontext.cc sp.cc \
-			sp_cache.cc parse_file.cc
+			sp_cache.cc parse_file.cc sql_trigger.cc
 gen_lex_hash_SOURCES =	gen_lex_hash.cc
 gen_lex_hash_LDADD =	$(LDADD) $(CXXLDFLAGS)
 mysql_tzinfo_to_sql_SOURCES =   mysql_tzinfo_to_sql.cc

sql/item.cc

@@ -24,6 +24,8 @@
 #include "my_dir.h"
 #include "sp_rcontext.h"
 #include "sql_acl.h"
+#include "sp_head.h"
+#include "sql_trigger.h"
 
 static void mark_as_dependent(THD *thd,
 			      SELECT_LEX *last, SELECT_LEX *current,
@@ -2381,6 +2383,97 @@ void Item_insert_value::print(String *str)
   str->append(')');
 }
 
+
+/*
+  Bind item representing field of row being changed in trigger
+  to appropriate Field object.
+
+  SYNOPSIS
+    setup_field()
+      thd   - current thread context
+      table - table of trigger (and where we looking for fields)
+      event - type of trigger event
+
+  NOTE
+    This function does almost the same as fix_fields() for Item_field
+    but is invoked during trigger definition parsing and takes TABLE
+    object as its argument.
+
+  RETURN VALUES
+    0	 ok
+    1	 field was not found.
+*/
+bool Item_trigger_field::setup_field(THD *thd, TABLE *table,
+                                     enum trg_event_type event)
+{
+  bool result= 1;
+  uint field_idx= (uint)-1;
+  bool save_set_query_id= thd->set_query_id;
+
+  /* TODO: Think more about consequences of this step. */
+  thd->set_query_id= 0;
+
+  if (find_field_in_real_table(thd, table, field_name,
+                                     strlen(field_name), 0, 0,
+                                     &field_idx))
+  {
+    field= (row_version == OLD_ROW && event == TRG_EVENT_UPDATE) ?
+             table->triggers->old_field[field_idx] :
+             table->field[field_idx];
+    result= 0;
+  }
+
+  thd->set_query_id= save_set_query_id;
+
+  return result;
+}
+
+
+bool Item_trigger_field::eq(const Item *item, bool binary_cmp) const
+{
+  return item->type() == TRIGGER_FIELD_ITEM &&
+         row_version == ((Item_trigger_field *)item)->row_version &&
+         !my_strcasecmp(system_charset_info, field_name,
+                        ((Item_trigger_field *)item)->field_name);
+}
+
+
+bool Item_trigger_field::fix_fields(THD *thd,
+                                    TABLE_LIST *table_list,
+                                    Item **items)
+{
+  /*
+    Since trigger is object tightly associated with TABLE object most
+    of its set up can be performed during trigger loading i.e. trigger
+    parsing! So we have little to do in fix_fields. :)
+    FIXME may be we still should bother about permissions here.
+  */
+  DBUG_ASSERT(fixed == 0);
+  // QQ: May be this should be moved to setup_field?
+  set_field(field);
+  fixed= 1;
+  return 0;
+}
+
+
+void Item_trigger_field::print(String *str)
+{
+  str->append((row_version == NEW_ROW) ? "NEW" : "OLD", 3);
+  str->append('.');
+  str->append(field_name);
+}
+
+
+void Item_trigger_field::cleanup()
+{
+  /*
+    Since special nature of Item_trigger_field we should not do most of
+    things from Item_field::cleanup() or Item_ident::cleanup() here.
+  */
+  Item::cleanup();
+}
+
+
 /*
   If item is a const function, calculate it and return a const item
   The original item is freed if not returned

sql/item.h

@@ -99,7 +99,7 @@ public:
 	     PROC_ITEM,COND_ITEM, REF_ITEM, FIELD_STD_ITEM,
 	     FIELD_VARIANCE_ITEM, INSERT_VALUE_ITEM,
              SUBSELECT_ITEM, ROW_ITEM, CACHE_ITEM, TYPE_HOLDER,
-             PARAM_ITEM};
+             PARAM_ITEM, TRIGGER_FIELD_ITEM};
 
   enum cond_result { COND_UNDEF,COND_OK,COND_TRUE,COND_FALSE };
   
@@ -440,6 +440,7 @@ public:
 
 class Item_field :public Item_ident
 {
+protected:
   void set_field(Field *field);
 public:
   Field *field,*result_field;
@@ -1196,6 +1197,57 @@ public:
   }
 };
 
+
+/*
+  We need this two enums here instead of sql_lex.h because
+  at least one of them is used by Item_trigger_field interface.
+
+  Time when trigger is invoked (i.e. before or after row actually
+  inserted/updated/deleted).
+*/
+enum trg_action_time_type
+{
+  TRG_ACTION_BEFORE= 0, TRG_ACTION_AFTER= 1
+};
+
+/*
+  Event on which trigger is invoked.
+*/
+enum trg_event_type
+{
+  TRG_EVENT_INSERT= 0 , TRG_EVENT_UPDATE= 1, TRG_EVENT_DELETE= 2
+};
+
+/*
+  Represents NEW/OLD version of field of row which is
+  changed/read in trigger.
+
+  Note: For this item actual binding to Field object happens not during
+        fix_fields() (like for Item_field) but during parsing of trigger
+        definition, when table is opened, with special setup_field() call.
+*/
+class Item_trigger_field : public Item_field
+{
+public:
+  /* Is this item represents row from NEW or OLD row ? */
+  enum row_version_type {OLD_ROW, NEW_ROW};
+  row_version_type row_version;
+
+  Item_trigger_field(row_version_type row_ver_par,
+                     const char *field_name_par):
+    Item_field((const char *)NULL, (const char *)NULL, field_name_par),
+    row_version(row_ver_par)
+  {}
+  bool setup_field(THD *thd, TABLE *table, enum trg_event_type event);
+  enum Type type() const { return TRIGGER_FIELD_ITEM; }
+  bool eq(const Item *item, bool binary_cmp) const;
+  bool fix_fields(THD *, struct st_table_list *, Item **);
+  void print(String *str);
+  table_map used_tables() const { return (table_map)0L; }
+  void cleanup();
+};
+
+
 class Item_cache: public Item
 {
 protected:

sql/item_func.cc

@@ -2563,6 +2563,16 @@ void Item_func_set_user_var::print(String *str)
 }
 
 
+void Item_func_set_user_var::print_as_stmt(String *str)
+{
+  str->append("set @", 5);
+  str->append(name.str, name.length);
+  str->append(":=", 2);
+  args[0]->print(str);
+  str->append(')');
+}
+
+
 String *
 Item_func_get_user_var::val_str(String *str)
 {
@@ -3312,6 +3322,11 @@ Item_func_sp::execute(Item **itp)
   sp_change_security_context(thd, m_sp, &save_ctx);
 #endif
 
+  /*
+    We don't need to surpress senfing of ok packet here (by setting
+    thd->net.no_send_ok to true), because we are not allowing statements
+    in functions now.
+  */
   res= m_sp->execute_function(thd, args, arg_count, itp);
 
 #ifndef NO_EMBEDDED_ACCESS_CHECKS

sql/item_func.h

@@ -945,6 +945,7 @@ public:
   bool fix_fields(THD *thd, struct st_table_list *tables, Item **ref);
   void fix_length_and_dec();
   void print(String *str);
+  void print_as_stmt(String *str);
   const char *func_name() const { return "set_user_var"; }
 };
 

sql/lex.h

@@ -167,6 +167,7 @@ static SYMBOL symbols[] = {
   { "DUMPFILE",		SYM(DUMPFILE)},
   { "DUPLICATE",	SYM(DUPLICATE_SYM)},
   { "DYNAMIC",		SYM(DYNAMIC_SYM)},
+  { "EACH",             SYM(EACH_SYM)},
   { "ELSE",             SYM(ELSE)},
   { "ELSEIF",           SYM(ELSEIF_SYM)},
   { "ENABLE",		SYM(ENABLE_SYM)},
@@ -470,6 +471,7 @@ static SYMBOL symbols[] = {
   { "TO",		SYM(TO_SYM)},
   { "TRAILING",		SYM(TRAILING)},
   { "TRANSACTION",	SYM(TRANSACTION_SYM)},
+  { "TRIGGER",          SYM(TRIGGER_SYM)},
   { "TRUE",		SYM(TRUE_SYM)},
   { "TRUNCATE",		SYM(TRUNCATE_SYM)},
   { "TYPE",		SYM(TYPE_SYM)},

sql/mysql_priv.h

@@ -472,6 +472,7 @@ int mysql_rm_table_part2_with_lock(THD *thd, TABLE_LIST *tables,
 				   bool log_query);
 int quick_rm_table(enum db_type base,const char *db,
 		   const char *table_name);
+void close_cached_table(THD *thd, TABLE *table);
 bool mysql_rename_tables(THD *thd, TABLE_LIST *table_list);
 bool mysql_change_db(THD *thd,const char *name);
 void mysql_parse(THD *thd,char *inBuf,uint length);
@@ -612,6 +613,7 @@ int mysql_prepare_delete(THD *thd, TABLE_LIST *table_list, Item **conds);
 int mysql_delete(THD *thd, TABLE_LIST *table, COND *conds, SQL_LIST *order,
                  ha_rows rows, ulong options);
 int mysql_truncate(THD *thd, TABLE_LIST *table_list, bool dont_send_ok=0);
+int mysql_create_or_drop_trigger(THD *thd, TABLE_LIST *tables, bool create);
 TABLE *open_ltable(THD *thd, TABLE_LIST *table_list, thr_lock_type update);
 TABLE *open_table(THD *thd, TABLE_LIST *table_list, MEM_ROOT* mem,
 		  bool *refresh);
@@ -640,6 +642,10 @@ find_field_in_table(THD *thd, TABLE_LIST *table_list,
                     bool check_grants_table, bool check_grants_view,
                     bool allow_rowid,
                     uint *cached_field_index_ptr);
+Field *
+find_field_in_real_table(THD *thd, TABLE *table, const char *name,
+                         uint length, bool check_grants, bool allow_rowid,
+                         uint *cached_field_index_ptr);
 #ifdef HAVE_OPENSSL
 #include <openssl/des.h>
 struct st_des_keyblock

sql/parse_file.cc

@@ -46,7 +46,7 @@ write_escaped_string(IO_CACHE *file, LEX_STRING *val_s)
   {
     /*
       Should be in sync with read_escaped_string() and
-      parse_quated_escaped_string()
+      parse_quoted_escaped_string()
     */
     switch(*ptr) {
     case '\\': // escape character
@@ -154,11 +154,10 @@ write_parameter(IO_CACHE *file, gptr base, File_option *parameter,
     LEX_STRING *str;
     while ((str= it++))
     {
-      num.set((ulonglong)str->length, &my_charset_bin);
-      // ',' after string to detect list continuation
+      // We need ' ' after string to detect list continuation
       if ((!first && my_b_append(file, (const byte *)" ", 1)) ||
 	  my_b_append(file, (const byte *)"\'", 1) ||
-	  my_b_append(file, (const byte *)str->str, str->length) ||
+          write_escaped_string(file, str) ||
 	  my_b_append(file, (const byte *)"\'", 1))
       {
 	DBUG_RETURN(TRUE);
@@ -486,7 +485,7 @@ read_escaped_string(char *ptr, char *eol, LEX_STRING *str)
 	return TRUE;
       /*
 	Should be in sync with write_escaped_string() and
-	parse_quated_escaped_string()
+	parse_quoted_escaped_string()
       */
       switch(*ptr) {
       case '\\':
@@ -562,7 +561,7 @@ parse_escaped_string(char *ptr, char *end, MEM_ROOT *mem_root, LEX_STRING *str)
 */
 
 static char *
-parse_quated_escaped_string(char *ptr, char *end,
+parse_quoted_escaped_string(char *ptr, char *end,
 			    MEM_ROOT *mem_root, LEX_STRING *str)
 {
   char *eol;
@@ -684,7 +683,6 @@ File_parser::parse(gptr base, MEM_ROOT *mem_root,
 	    my_error(ER_FPARSER_ERROR_IN_PARAMETER, MYF(0),
 		     parameter->name.str, line);
 	    DBUG_RETURN(TRUE);
-	    DBUG_RETURN(TRUE);
 	  }
 	  break;
 	}
@@ -724,6 +722,7 @@ File_parser::parse(gptr base, MEM_ROOT *mem_root,
 	  /*
 	    TODO: remove play with mem_root, when List will be able
 	    to store MEM_ROOT* pointer for list elements allocation
+            FIXME: we can't handle empty lists
 	  */
 	  sql_mem= my_pthread_getspecific_ptr(MEM_ROOT*, THR_MALLOC);
 	  list= (List<LEX_STRING>*)(base + parameter->offset);
@@ -741,7 +740,7 @@ File_parser::parse(gptr base, MEM_ROOT *mem_root,
 					       sizeof(LEX_STRING))) ||
 		list->push_back(str))
 	      goto list_err;
-	    if(!(ptr= parse_quated_escaped_string(ptr, end, mem_root, str)))
+	    if(!(ptr= parse_quoted_escaped_string(ptr, end, mem_root, str)))
 	      goto list_err_w_message;
 	    switch (*ptr) {
 	    case '\n':

sql/parse_file.h

@@ -27,7 +27,8 @@ enum file_opt_type {
   FILE_OPTIONS_REV,		/* Revision version number (ulonglong) */
   FILE_OPTIONS_TIMESTAMP,	/* timestamp (LEX_STRING have to be
 				   allocated with length 20 (19+1) */
-  FILE_OPTIONS_STRLIST		/* list of strings (List<char*>) */
+  FILE_OPTIONS_STRLIST          /* list of escaped strings
+                                   (List<LEX_STRING>) */
 };
 
 struct File_option

sql/share/czech/errmsg.txt

@@ -370,3 +370,8 @@ character-set=latin2
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
 "GOTO is not allowed in a stored procedure handler"
+"Trigger already exists"
+"Trigger does not exist"
+"Trigger's '%-.64s' is view or temporary table"
+"Updating of %s row is not allowed in %strigger"
+"There is no %s row in %s trigger"

sql/share/danish/errmsg.txt

@@ -364,3 +364,8 @@ character-set=latin1
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
 "GOTO is not allowed in a stored procedure handler"
+"Trigger already exists"
+"Trigger does not exist"
+"Trigger's '%-.64s' is view or temporary table"
+"Updating of %s row is not allowed in %strigger"
+"There is no %s row in %s trigger"

sql/share/dutch/errmsg.txt

@@ -372,3 +372,8 @@ character-set=latin1
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
 "GOTO is not allowed in a stored procedure handler"
+"Trigger already exists"
+"Trigger does not exist"
+"Trigger's '%-.64s' is view or temporary table"
+"Updating of %s row is not allowed in %strigger"
+"There is no %s row in %s trigger"

sql/share/english/errmsg.txt

@@ -361,3 +361,8 @@ character-set=latin1
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
 "GOTO is not allowed in a stored procedure handler"
+"Trigger already exists"
+"Trigger does not exist"
+"Trigger's '%-.64s' is view or temporary table"
+"Updating of %s row is not allowed in %strigger"
+"There is no %s row in %s trigger"

sql/share/estonian/errmsg.txt

@@ -366,3 +366,8 @@ character-set=latin7
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
 "GOTO is not allowed in a stored procedure handler"
+"Trigger already exists"
+"Trigger does not exist"
+"Trigger's '%-.64s' is view or temporary table"
+"Updating of %s row is not allowed in %strigger"
+"There is no %s row in %s trigger"

sql/share/french/errmsg.txt

@@ -361,3 +361,8 @@ character-set=latin1
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
 "GOTO is not allowed in a stored procedure handler"
+"Trigger already exists"
+"Trigger does not exist"
+"Trigger's '%-.64s' is view or temporary table"
+"Updating of %s row is not allowed in %strigger"
+"There is no %s row in %s trigger"

sql/share/german/errmsg.txt

@@ -373,3 +373,8 @@ character-set=latin1
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
 "GOTO is not allowed in a stored procedure handler"
+"Trigger already exists"
+"Trigger does not exist"
+"Trigger's '%-.64s' is view or temporary table"
+"Updating of %s row is not allowed in %strigger"
+"There is no %s row in %s trigger"

sql/share/greek/errmsg.txt

@@ -361,3 +361,8 @@ character-set=greek
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
 "GOTO is not allowed in a stored procedure handler"
+"Trigger already exists"
+"Trigger does not exist"
+"Trigger's '%-.64s' is view or temporary table"
+"Updating of %s row is not allowed in %strigger"
+"There is no %s row in %s trigger"

sql/share/hungarian/errmsg.txt

@@ -363,3 +363,8 @@ character-set=latin2
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
 "GOTO is not allowed in a stored procedure handler"
+"Trigger already exists"
+"Trigger does not exist"
+"Trigger's '%-.64s' is view or temporary table"
+"Updating of %s row is not allowed in %strigger"
+"There is no %s row in %s trigger"

sql/share/italian/errmsg.txt

@@ -361,3 +361,8 @@ character-set=latin1
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
 "GOTO is not allowed in a stored procedure handler"
+"Trigger already exists"
+"Trigger does not exist"
+"Trigger's '%-.64s' is view or temporary table"
+"Updating of %s row is not allowed in %strigger"
+"There is no %s row in %s trigger"

sql/share/japanese/errmsg.txt

@@ -363,3 +363,8 @@ character-set=ujis
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
 "GOTO is not allowed in a stored procedure handler"
+"Trigger already exists"
+"Trigger does not exist"
+"Trigger's '%-.64s' is view or temporary table"
+"Updating of %s row is not allowed in %strigger"
+"There is no %s row in %s trigger"

sql/share/korean/errmsg.txt

@@ -361,3 +361,8 @@ character-set=euckr
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
 "GOTO is not allowed in a stored procedure handler"
+"Trigger already exists"
+"Trigger does not exist"
+"Trigger's '%-.64s' is view or temporary table"
+"Updating of %s row is not allowed in %strigger"
+"There is no %s row in %s trigger"

sql/share/norwegian-ny/errmsg.txt

@@ -363,3 +363,8 @@ character-set=latin1
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
 "GOTO is not allowed in a stored procedure handler"
+"Trigger already exists"
+"Trigger does not exist"
+"Trigger's '%-.64s' is view or temporary table"
+"Updating of %s row is not allowed in %strigger"
+"There is no %s row in %s trigger"

sql/share/norwegian/errmsg.txt

@@ -363,3 +363,8 @@ character-set=latin1
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
 "GOTO is not allowed in a stored procedure handler"
+"Trigger already exists"
+"Trigger does not exist"
+"Trigger's '%-.64s' is view or temporary table"
+"Updating of %s row is not allowed in %strigger"
+"There is no %s row in %s trigger"

sql/share/polish/errmsg.txt

@@ -365,3 +365,8 @@ character-set=latin2
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
 "GOTO is not allowed in a stored procedure handler"
+"Trigger already exists"
+"Trigger does not exist"
+"Trigger's '%-.64s' is view or temporary table"
+"Updating of %s row is not allowed in %strigger"
+"There is no %s row in %s trigger"

sql/share/portuguese/errmsg.txt

@@ -362,3 +362,8 @@ character-set=latin1
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
 "GOTO is not allowed in a stored procedure handler"
+"Trigger already exists"
+"Trigger does not exist"
+"Trigger's '%-.64s' is view or temporary table"
+"Updating of %s row is not allowed in %strigger"
+"There is no %s row in %s trigger"

sql/share/romanian/errmsg.txt

@@ -365,3 +365,8 @@ character-set=latin2
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
 "GOTO is not allowed in a stored procedure handler"
+"Trigger already exists"
+"Trigger does not exist"
+"Trigger's '%-.64s' is view or temporary table"
+"Updating of %s row is not allowed in %strigger"
+"There is no %s row in %s trigger"

sql/share/russian/errmsg.txt

@@ -360,6 +360,11 @@ character-set=koi8r
 "View SELECT    view    "
 "  view      (  )"
 " view       ()"
-"View '%-.64s.%-.64s'      "
+"View '%-.64s.%-.64s'      "
 "Can't drop a %s from within another stored routine"
 "GOTO is not allowed in a stored procedure handler"
+"Trigger already exists"
+"Trigger does not exist"
+"Trigger's '%-.64s' is view or temporary table"
+"Updating of %s row is not allowed in %strigger"
+"There is no %s row in %s trigger"

sql/share/serbian/errmsg.txt

@@ -367,3 +367,8 @@ character-set=cp1250
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
 "GOTO is not allowed in a stored procedure handler"
+"Trigger already exists"
+"Trigger does not exist"
+"Trigger's '%-.64s' is view or temporary table"
+"Updating of %s row is not allowed in %strigger"
+"There is no %s row in %s trigger"

sql/share/slovak/errmsg.txt

@@ -369,3 +369,8 @@ character-set=latin2
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
 "GOTO is not allowed in a stored procedure handler"
+"Trigger already exists"
+"Trigger does not exist"
+"Trigger's '%-.64s' is view or temporary table"
+"Updating of %s row is not allowed in %strigger"
+"There is no %s row in %s trigger"

sql/share/spanish/errmsg.txt

@@ -363,3 +363,8 @@ character-set=latin1
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
 "GOTO is not allowed in a stored procedure handler"
+"Trigger already exists"
+"Trigger does not exist"
+"Trigger's '%-.64s' is view or temporary table"
+"Updating of %s row is not allowed in %strigger"
+"There is no %s row in %s trigger"

sql/share/swedish/errmsg.txt

@@ -361,3 +361,8 @@ character-set=latin1
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
 "GOTO is not allowed in a stored procedure handler"
+"Trigger already exists"
+"Trigger does not exist"
+"Trigger's '%-.64s' is view or temporary table"
+"Updating of %s row is not allowed in %strigger"
+"There is no %s row in %s trigger"

sql/share/ukrainian/errmsg.txt

@@ -366,3 +366,8 @@ character-set=koi8u
 "View '%-.64s.%-.64s'   Ŧަ æ  æ"
 "Can't drop a %s from within another stored routine"
 "GOTO is not allowed in a stored procedure handler"
+"Trigger already exists"
+"Trigger does not exist"
+"Trigger's '%-.64s' is view or temporary table"
+"Updating of %s row is not allowed in %strigger"
+"There is no %s row in %s trigger"

sql/sp_head.cc

@@ -292,10 +292,13 @@ sp_head::init_strings(THD *thd, LEX *lex, sp_name *name)
   /* During parsing, we must use thd->mem_root */
   MEM_ROOT *root= &thd->mem_root;
 
+  /* We have to copy strings to get them into the right memroot */
+  if (name)
+  {
     DBUG_PRINT("info", ("name: %*.s%*s",
                         name->m_db.length, name->m_db.str,
 		        name->m_name.length, name->m_name.str));
-  /* We have to copy strings to get them into the right memroot */
+    
     if (name->m_db.length == 0)
     {
       m_db.length= (thd->db ? strlen(thd->db) : 0);
@@ -313,10 +316,19 @@ sp_head::init_strings(THD *thd, LEX *lex, sp_name *name)
       name->init_qname(thd);
     m_qname.length= name->m_qname.length;
     m_qname.str= strmake_root(root, name->m_qname.str, m_qname.length);
+  }
+  else
+  {
+    m_db.length= (thd->db ? strlen(thd->db) : 0);
+    m_db.str= strmake_root(root, (thd->db ? thd->db : ""), m_db.length);
+  }
   
-  m_params.length= m_param_end- m_param_begin;
+  if (m_param_begin && m_param_end)
+  {
+    m_params.length= m_param_end - m_param_begin;
     m_params.str= strmake_root(root,
                                (char *)m_param_begin, m_params.length);
+  }
   if (m_returns_begin && m_returns_end)
   {
     /* QQ KLUDGE: We can't seem to cut out just the type in the parser
@@ -579,8 +591,10 @@ sp_head::execute_function(THD *thd, Item **argp, uint argcount, Item **resp)
   thd->spcont= nctx;
 
   ret= execute(thd);
-  if (ret == 0)
+
+  if (m_type == TYPE_ENUM_FUNCTION && ret == 0)
   {
+    /* We need result only in function but not in trigger */
     Item *it= nctx->get_result();
 
     if (it)
@@ -767,6 +781,9 @@ sp_head::reset_lex(THD *thd)
   /* And keep the SP stuff too */
   sublex->sphead= oldlex->sphead;
   sublex->spcont= oldlex->spcont;
+  /* And trigger related stuff too */
+  sublex->trg_chistics= oldlex->trg_chistics;
+  sublex->trg_table= oldlex->trg_table;
   sublex->sp_lex_in_use= FALSE;
   DBUG_VOID_RETURN;
 }
@@ -1228,6 +1245,60 @@ sp_instr_set::print(String *str)
   m_value->print(str);
 }
 
+//
+// sp_instr_set_user_var
+//
+int
+sp_instr_set_user_var::execute(THD *thd, uint *nextp)
+{
+  int res= 0;
+
+  DBUG_ENTER("sp_instr_set_user_var::execute");
+  /*
+    It is ok to pass 0 as 3rd argument to fix_fields() since
+    Item_func_set_user_var::fix_fields() won't use it.
+    QQ: Still unsure what should we return in case of error 1 or -1 ?
+  */
+  if (!m_set_var_item.fixed && m_set_var_item.fix_fields(thd, 0, 0) ||
+      m_set_var_item.check() || m_set_var_item.update())
+    res= -1;
+  *nextp= m_ip + 1;
+  DBUG_RETURN(res);
+}
+
+void
+sp_instr_set_user_var::print(String *str)
+{
+  m_set_var_item.print_as_stmt(str);
+}
+
+//
+// sp_instr_set_trigger_field
+//
+int
+sp_instr_set_trigger_field::execute(THD *thd, uint *nextp)
+{
+  int res= 0;
+
+  DBUG_ENTER("sp_instr_set_trigger_field::execute");
+  /* QQ: Still unsure what should we return in case of error 1 or -1 ? */
+  if (!value->fixed && value->fix_fields(thd, 0, &value) ||
+      trigger_field.fix_fields(thd, 0, 0) ||
+      (value->save_in_field(trigger_field.field, 0) < 0))
+    res= -1;
+  *nextp= m_ip + 1;
+  DBUG_RETURN(res);
+}
+
+void
+sp_instr_set_trigger_field::print(String *str)
+{
+  str->append("set ", 4);
+  trigger_field.print(str);
+  str->append(":=", 2);
+  value->print(str);
+}
+
 //
 // sp_instr_jump
 //

sql/sp_head.h

@@ -28,6 +28,7 @@
 // in the CREATE TABLE command.
 #define TYPE_ENUM_FUNCTION  1
 #define TYPE_ENUM_PROCEDURE 2
+#define TYPE_ENUM_TRIGGER   3
 
 Item_result
 sp_map_result_type(enum enum_field_types type);
@@ -377,6 +378,71 @@ private:
 }; // class sp_instr_set : public sp_instr
 
 
+/*
+  Set user variable instruction.
+  Used in functions and triggers to set user variables because we don't
+  want use sp_instr_stmt + "SET @a:=..." statement in this case since
+  latter will close all tables and thus will ruin execution of statement
+  calling/invoking this function/trigger.
+*/
+class sp_instr_set_user_var : public sp_instr
+{
+  sp_instr_set_user_var(const sp_instr_set_user_var &);
+  void operator=(sp_instr_set_user_var &);
+
+public:
+
+  sp_instr_set_user_var(uint ip, LEX_STRING var, Item *val)
+    : sp_instr(ip), m_set_var_item(var, val)
+  {}
+
+  virtual ~sp_instr_set_user_var()
+  {}
+
+  virtual int execute(THD *thd, uint *nextp);
+
+  virtual void print(String *str);
+
+private:
+
+  Item_func_set_user_var m_set_var_item;
+}; // class sp_instr_set_user_var : public sp_instr
+
+
+/*
+  Set NEW/OLD row field value instruction. Used in triggers.
+*/
+class sp_instr_set_trigger_field : public sp_instr
+{
+  sp_instr_set_trigger_field(const sp_instr_set_trigger_field &);
+  void operator=(sp_instr_set_trigger_field &);
+
+public:
+
+  sp_instr_set_trigger_field(uint ip, LEX_STRING field_name, Item *val)
+    : sp_instr(ip),
+      trigger_field(Item_trigger_field::NEW_ROW, field_name.str),
+      value(val)
+  {}
+
+  virtual ~sp_instr_set_trigger_field()
+  {}
+
+  virtual int execute(THD *thd, uint *nextp);
+
+  virtual void print(String *str);
+
+  bool setup_field(THD *thd, TABLE *table, enum trg_event_type event)
+  {
+    return trigger_field.setup_field(thd, table, event);
+  }
+private:
+
+  Item_trigger_field trigger_field;
+  Item *value;
+}; // class sp_instr_trigger_field : public sp_instr
+
+
 class sp_instr_jump : public sp_instr
 {
   sp_instr_jump(const sp_instr_jump &);	/* Prevent use of these */

sql/sql_base.cc

@@ -20,6 +20,8 @@
 #include "mysql_priv.h"
 #include "sql_acl.h"
 #include "sql_select.h"
+#include "sp_head.h"
+#include "sql_trigger.h"
 #include <m_ctype.h>
 #include <my_dir.h>
 #include <hash.h>
@@ -42,10 +44,6 @@ static my_bool open_new_frm(const char *path, const char *alias,
 			    uint db_stat, uint prgflag,
 			    uint ha_open_flags, TABLE *outparam,
 			    TABLE_LIST *table_desc, MEM_ROOT *mem_root);
-static Field *find_field_in_real_table(THD *thd, TABLE *table,
-				       const char *name, uint length,
-				       bool check_grants, bool allow_rowid, 
-				       uint *cached_field_index_ptr);
 
 extern "C" byte *table_cache_key(const byte *record,uint *length,
 				 my_bool not_used __attribute__((unused)))
@@ -210,6 +208,7 @@ OPEN_TABLE_LIST *list_open_tables(THD *thd, const char *wild)
 void intern_close_table(TABLE *table)
 {						// Free all structures
   free_io_cache(table);
+  delete table->triggers;
   if (table->file)
     VOID(closefrm(table));			// close file
 }
@@ -747,6 +746,7 @@ TABLE *reopen_name_locked_table(THD* thd, TABLE_LIST* table_list)
       !(table->table_cache_key =memdup_root(&table->mem_root,(char*) key,
 					    key_length)))
   {
+    delete table->triggers;
     closefrm(table);
     pthread_mutex_unlock(&LOCK_open);
     DBUG_RETURN(0);
@@ -1010,6 +1010,7 @@ bool reopen_table(TABLE *table,bool locked)
   if (!(tmp.table_cache_key= memdup_root(&tmp.mem_root,db,
 					 table->key_length)))
   {
+    delete tmp.triggers;
     closefrm(&tmp);				// End of memory
     goto end;
   }
@@ -1038,6 +1039,7 @@ bool reopen_table(TABLE *table,bool locked)
   tmp.next=		table->next;
   tmp.prev=		table->prev;
 
+  delete table->triggers;
   if (table->file)
     VOID(closefrm(table));		// close file, free everything
 
@@ -1424,6 +1426,9 @@ static int open_unireg_entry(THD *thd, TABLE *entry, const char *db,
   if (error == 5)
     DBUG_RETURN(0);	// we have just opened VIEW
 
+  if (Table_triggers_list::check_n_load(thd, db, name, entry))
+    goto err;
+
   /*
     If we are here, there was no fatal error (but error may be still
     unitialized).
@@ -1452,6 +1457,7 @@ static int open_unireg_entry(THD *thd, TABLE *entry, const char *db,
         */
         sql_print_error("Error: when opening HEAP table, could not allocate \
 memory to write 'DELETE FROM `%s`.`%s`' to the binary log",db,name);
+        delete entry->triggers;
         if (entry->file)
           closefrm(entry);
         goto err;
@@ -1983,7 +1989,7 @@ find_field_in_table(THD *thd, TABLE_LIST *table_list,
     #			pointer to field
 */
 
-static Field *find_field_in_real_table(THD *thd, TABLE *table,
+Field *find_field_in_real_table(THD *thd, TABLE *table,
                                 const char *name, uint length,
                                 bool check_grants, bool allow_rowid,
                                 uint *cached_field_index_ptr)

sql/sql_delete.cc

@@ -26,6 +26,8 @@
 #include "mysql_priv.h"
 #include "ha_innodb.h"
 #include "sql_select.h"
+#include "sp_head.h"
+#include "sql_trigger.h"
 
 int mysql_delete(THD *thd, TABLE_LIST *table_list, COND *conds, SQL_LIST *order,
                  ha_rows limit, ulong options)
@@ -160,6 +162,11 @@ int mysql_delete(THD *thd, TABLE_LIST *table_list, COND *conds, SQL_LIST *order,
     // thd->net.report_error is tested to disallow delete row on error
     if (!(select && select->skip_record())&& !thd->net.report_error )
     {
+
+      if (table->triggers)
+        table->triggers->process_triggers(thd, TRG_EVENT_DELETE,
+                                          TRG_ACTION_BEFORE);
+
       if (!(error=table->file->delete_row(table->record[0])))
       {
 	deleted++;
@@ -183,6 +190,10 @@ int mysql_delete(THD *thd, TABLE_LIST *table_list, COND *conds, SQL_LIST *order,
  	error= 1;
 	break;
       }
+
+      if (table->triggers)
+        table->triggers->process_triggers(thd, TRG_EVENT_DELETE,
+                                          TRG_ACTION_AFTER);
     }
     else
       table->file->unlock_row();  // Row failed selection, release lock on it

sql/sql_insert.cc

@@ -19,6 +19,8 @@
 
 #include "mysql_priv.h"
 #include "sql_acl.h"
+#include "sp_head.h"
+#include "sql_trigger.h"
 
 static int check_null_fields(THD *thd,TABLE *entry);
 #ifndef EMBEDDED_LIBRARY
@@ -302,6 +304,12 @@ int mysql_insert(THD *thd,TABLE_LIST *table_list,
 	break;
       }
     }
+
+    // FIXME: Actually we should do this before check_null_fields.
+    //        Or even go into write_record ?
+    if (table->triggers)
+      table->triggers->process_triggers(thd, TRG_EVENT_INSERT, TRG_ACTION_BEFORE);
+
 #ifndef EMBEDDED_LIBRARY
     if (lock_type == TL_WRITE_DELAYED)
     {
@@ -324,6 +332,9 @@ int mysql_insert(THD *thd,TABLE_LIST *table_list,
       id= thd->last_insert_id;
     }
     thd->row_count++;
+
+    if (table->triggers)
+      table->triggers->process_triggers(thd, TRG_EVENT_INSERT, TRG_ACTION_AFTER);
   }
 
   /*

sql/sql_lex.cc

@@ -24,6 +24,12 @@
 #include "sp.h"
 #include "sp_head.h"
 
+/*
+  We are using pointer to this variable for distinguishing between assignment
+  to NEW row field (when parsing trigger definition) and structured variable.
+*/
+sys_var_long_ptr trg_new_row_fake_var(0, 0);
+
 /* Macros to look like lex */
 
 #define yyGet()		*(lex->ptr++)
@@ -129,6 +135,7 @@ void lex_start(THD *thd, uchar *buf,uint length)
   lex->duplicates= DUP_ERROR;
   lex->sphead= NULL;
   lex->spcont= NULL;
+  lex->trg_table= NULL;
 
   extern byte *sp_lex_spfuns_key(const byte *ptr, uint *plen, my_bool first);
   hash_free(&lex->spfuns);

sql/sql_lex.h

@@ -85,6 +85,7 @@ enum enum_sql_command {
   SQLCOM_SHOW_STATUS_PROC, SQLCOM_SHOW_STATUS_FUNC,
   SQLCOM_PREPARE, SQLCOM_EXECUTE, SQLCOM_DEALLOCATE_PREPARE,
   SQLCOM_CREATE_VIEW, SQLCOM_DROP_VIEW,
+  SQLCOM_CREATE_TRIGGER, SQLCOM_DROP_TRIGGER,
   /* This should be the last !!! */
   SQLCOM_END
 };
@@ -608,6 +609,15 @@ struct st_sp_chistics
   bool detistic;
 };
 
+
+struct st_trg_chistics
+{
+  enum trg_action_time_type action_time;
+  enum trg_event_type event;
+};
+
+extern sys_var_long_ptr trg_new_row_fake_var;
+
 /* The state of the lex parsing. This is saved in the THD struct */
 
 typedef struct st_lex
@@ -713,6 +723,14 @@ typedef struct st_lex
     rexecuton
   */
   bool empty_field_list_on_rset;
+  /* Characterstics of trigger being created */
+  st_trg_chistics trg_chistics;
+  /*
+    Points to table being opened when we are parsing trigger definition
+    while opening table. 0 if we are parsing user provided CREATE TRIGGER
+    or any other statement. Used for NEW/OLD row field lookup in trigger.
+  */
+  TABLE *trg_table;
 
   st_lex()
   {

sql/sql_parse.cc

@@ -3837,6 +3837,20 @@ purposes internal to the MySQL server", MYF(0));
       res= mysql_drop_view(thd, first_table, thd->lex->drop_mode);
       break;
     }
+  case SQLCOM_CREATE_TRIGGER:
+  {
+    /* We don't care much about trigger body at that point */
+    delete lex->sphead;
+    lex->sphead= 0;
+
+    res= mysql_create_or_drop_trigger(thd, all_tables, 1);
+    break;
+  }
+  case SQLCOM_DROP_TRIGGER:
+  {
+    res= mysql_create_or_drop_trigger(thd, all_tables, 0);
+    break;
+  }
   default:					/* Impossible */
     send_ok(thd);
     break;

sql/sql_table.cc

@@ -1509,7 +1509,7 @@ static void wait_while_table_is_used(THD *thd,TABLE *table,
     Win32 clients must also have a WRITE LOCK on the table !
 */
 
-static bool close_cached_table(THD *thd, TABLE *table)
+void close_cached_table(THD *thd, TABLE *table)
 {
   DBUG_ENTER("close_cached_table");
 
@@ -1525,7 +1525,6 @@ static bool close_cached_table(THD *thd, TABLE *table)
 
   /* When lock on LOCK_open is freed other threads can continue */
   pthread_cond_broadcast(&COND_refresh);
-  DBUG_RETURN(0);
 }
 
 static int send_check_errmsg(THD *thd, TABLE_LIST* table,
@@ -3131,12 +3130,7 @@ int mysql_alter_table(THD *thd,char *new_db, char *new_name,
       close the original table at before doing the rename
     */
     table_name=thd->strdup(table_name);		// must be saved
-    if (close_cached_table(thd, table))
-    {						// Aborted
-      VOID(quick_rm_table(new_db_type,new_db,tmp_name));
-      VOID(pthread_mutex_unlock(&LOCK_open));
-      goto err;
-    }
+    close_cached_table(thd, table);
     table=0;					// Marker that table is closed
   }
 #if (!defined( __WIN__) && !defined( __EMX__) && !defined( OS2))

sql/sql_trigger.h

+/*
+  This class holds all information about triggers of table.
+
+  QQ: Will it be merged into TABLE in future ?
+*/
+class Table_triggers_list: public Sql_alloc
+{
+  /* Triggers as SPs grouped by event, action_time */
+  sp_head           *bodies[3][2];
+  /*
+    Copy of TABLE::Field array with field pointers set to old version
+    of record, used for OLD values in trigger on UPDATE.
+  */
+  Field             **old_field;
+  /*
+    Names of triggers.
+    Should correspond to order of triggers on definitions_list,
+    used in CREATE/DROP TRIGGER for looking up trigger by name.
+  */
+  List<LEX_STRING>  names_list;
+
+public:
+  /*
+    Field responsible for storing triggers definitions in file.
+    It have to be public because we are using it directly from parser.
+  */
+  List<LEX_STRING>  definitions_list;
+
+  Table_triggers_list():
+    old_field(0)
+  {
+    bzero((char *)bodies, sizeof(bodies));
+  }
+  ~Table_triggers_list();
+
+  bool create_trigger(THD *thd, TABLE_LIST *table);
+  bool drop_trigger(THD *thd, TABLE_LIST *table);
+  bool process_triggers(THD *thd, trg_event_type event,
+                        trg_action_time_type time_type)
+  {
+    int res= 0;
+
+    if (bodies[event][time_type])
+    {
+      /*
+        Similar to function invocation we don't need to surpress sending of
+        ok packets here because don't allow execute statements from trigger.
+
+        FIXME: We should juggle with security context here (because trigger
+        should be invoked with creator rights).
+      */
+      res= bodies[event][time_type]->execute_function(thd, 0, 0, 0);
+    }
+
+    return res;
+  }
+
+  static bool check_n_load(THD *thd, const char *db, const char *table_name,
+                           TABLE *table);
+
+  friend class Item_trigger_field;
+};

sql/sql_update.cc

@@ -23,6 +23,8 @@
 #include "mysql_priv.h"
 #include "sql_acl.h"
 #include "sql_select.h"
+#include "sp_head.h"
+#include "sql_trigger.h"
 
 static bool safe_update_on_fly(JOIN_TAB *join_tab, List<Item> *fields);
 
@@ -354,6 +356,10 @@ int mysql_update(THD *thd,
       if (fill_record(fields,values, 0) || thd->net.report_error)
 	break; /* purecov: inspected */
       found++;
+
+      if (table->triggers)
+        table->triggers->process_triggers(thd, TRG_EVENT_UPDATE, TRG_ACTION_BEFORE);
+
       if (compare_record(table, query_id))
       {
 	if (!(error=table->file->update_row((byte*) table->record[1],
@@ -369,6 +375,10 @@ int mysql_update(THD *thd,
 	  break;
 	}
       }
+
+      if (table->triggers)
+        table->triggers->process_triggers(thd, TRG_EVENT_UPDATE, TRG_ACTION_AFTER);
+
       if (!--limit && using_limit)
       {
 	error= -1;				// Simulate end of file

sql/table.h

@@ -73,6 +73,7 @@ typedef struct st_filesort_info
 
 class Field_timestamp;
 class Field_blob;
+class Table_triggers_list;
 
 struct st_table {
   handler *file;
@@ -154,6 +155,8 @@ struct st_table {
   REGINFO reginfo;			/* field connections */
   MEM_ROOT mem_root;
   GRANT_INFO grant;
+  /* Table's triggers, 0 if there are no of them */
+  Table_triggers_list *triggers;
 
   char		*table_cache_key;
   char		*table_name,*real_name,*path;