From d4b20f4a86aee448ed547be52d91001ada422319 Mon Sep 17 00:00:00 2001
From: "dlenev@brandersnatch.localdomain" <>
Date: Sun, 27 Mar 2005 16:15:21 +0400
Subject: [PATCH] Fix for bugs #5859 "DROP TABLE does not drop triggers" and
 #6559 "DROP DATABASE forgets to drop triggers".

If we drop table we should also drop all triggers associated with it.
To do this we have to check for existence of .TRG file when we are
dropping table and delete it too.
---
 mysql-test/r/trigger.result | 16 ++++++++++++++++
 mysql-test/t/trigger.test   | 20 ++++++++++++++++++++
 sql/handler.cc              |  1 +
 sql/mysql_priv.h            |  1 +
 sql/sql_table.cc            | 12 ++++++++++++
 sql/sql_trigger.cc          |  3 ++-
 6 files changed, 52 insertions(+), 1 deletion(-)

diff --git a/mysql-test/r/trigger.result b/mysql-test/r/trigger.result
index 4a85097cfce..cf0e0e8f564 100644
--- a/mysql-test/r/trigger.result
+++ b/mysql-test/r/trigger.result
@@ -1,5 +1,6 @@
 drop table if exists t1, t2;
 drop view if exists v1;
+drop database if exists mysqltest;
 create table t1 (i int);
 create trigger trg before insert on t1 for each row set @a:=1;
 set @a:=0;
@@ -190,3 +191,18 @@ select @del_before, @del_after;
 drop trigger t1.trg1;
 drop trigger t1.trg2;
 drop table t1;
+create table t1 (a int);
+create trigger trg1 before insert on t1 for each row set new.a= 10;
+drop table t1;
+create table t1 (a int);
+insert into t1 values ();
+select * from t1;
+a
+NULL
+drop table t1;
+create database mysqltest;
+use mysqltest;
+create table t1 (i int);
+create trigger trg1 before insert on t1 for each row set @a:= 1;
+drop database mysqltest;
+use test;
diff --git a/mysql-test/t/trigger.test b/mysql-test/t/trigger.test
index bf75f09d553..53144cf3591 100644
--- a/mysql-test/t/trigger.test
+++ b/mysql-test/t/trigger.test
@@ -5,6 +5,7 @@
 --disable_warnings
 drop table if exists t1, t2;
 drop view if exists v1;
+drop database if exists mysqltest;
 --enable_warnings
 
 create table t1 (i int);
@@ -229,3 +230,22 @@ select @del_before, @del_after;
 drop trigger t1.trg1;
 drop trigger t1.trg2;
 drop table t1;
+
+# Test for bug #5859 "DROP TABLE does not drop triggers". Trigger should not
+# magically reappear when we recreate dropped table.
+create table t1 (a int);
+create trigger trg1 before insert on t1 for each row set new.a= 10;
+drop table t1;
+create table t1 (a int);
+insert into t1 values ();
+select * from t1;
+drop table t1;
+
+# Test for bug #6559 "DROP DATABASE forgets to drop triggers". 
+create database mysqltest;
+use mysqltest;
+create table t1 (i int);
+create trigger trg1 before insert on t1 for each row set @a:= 1;
+# This should succeed
+drop database mysqltest;
+use test;
diff --git a/sql/handler.cc b/sql/handler.cc
index 4a01003f418..88b5fcef2c6 100644
--- a/sql/handler.cc
+++ b/sql/handler.cc
@@ -2366,6 +2366,7 @@ TYPELIB *ha_known_exts(void)
 
     known_extensions_id= mysys_usage_id;
     found_exts.push_back((char*) ".db");
+    found_exts.push_back((char*) triggers_file_ext);
     for (types= sys_table_types; types->type; types++)
     {      
       if (*types->value == SHOW_OPTION_YES)
diff --git a/sql/mysql_priv.h b/sql/mysql_priv.h
index 7e4c6675e45..2685da9780b 100644
--- a/sql/mysql_priv.h
+++ b/sql/mysql_priv.h
@@ -1044,6 +1044,7 @@ extern const char *first_keyword, *my_localhost, *delayed_user, *binary_keyword;
 extern const char **errmesg;			/* Error messages */
 extern const char *myisam_recover_options_str;
 extern const char *in_left_expr_name, *in_additional_cond;
+extern const char * const triggers_file_ext;
 extern Eq_creator eq_creator;
 extern Ne_creator ne_creator;
 extern Gt_creator gt_creator;
diff --git a/sql/sql_table.cc b/sql/sql_table.cc
index b125eeaf03a..14b57cf580f 100644
--- a/sql/sql_table.cc
+++ b/sql/sql_table.cc
@@ -257,7 +257,19 @@ int mysql_rm_table_part2(THD *thd, TABLE_LIST *tables, bool if_exists,
 	/* Delete the table definition file */
 	strmov(end,reg_ext);
 	if (!(new_error=my_delete(path,MYF(MY_WME))))
+        {
 	  some_tables_deleted=1;
+          /*
+            Destroy triggers for this table if there are any.
+
+            We won't need this as soon as we will have new .FRM format,
+            in which we will store trigger definitions in the same .FRM
+            files as table descriptions.
+          */
+          strmov(end, triggers_file_ext);
+          if (!access(path, F_OK))
+            new_error= my_delete(path, MYF(MY_WME));
+        }
         error|= new_error;
       }
     }
diff --git a/sql/sql_trigger.cc b/sql/sql_trigger.cc
index 110841e8fd4..5b6f12eab52 100644
--- a/sql/sql_trigger.cc
+++ b/sql/sql_trigger.cc
@@ -4,7 +4,8 @@
 #include "parse_file.h"
 
 static const LEX_STRING triggers_file_type= {(char *)"TRIGGERS", 8};
-static const char * const triggers_file_ext= ".TRG";
+
+const char * const triggers_file_ext= ".TRG";
 
 /*
   Table of .TRG file field descriptors.