Merge mysql.com:/home/mydev/mysql-5.0

into  mysql.com:/home/mydev/mysql-5.0-bug5390

mysql-test/r/lock.result

@@ -47,6 +47,17 @@ unlock tables;
 lock tables t1 write, t1 as t1_alias read;
 insert into t1 select index1,nr from t1 as t1_alias;
 drop table t1,t2;
+create table t1 (c1 int);
+create table t2 (c1 int);
+create table t3 (c1 int);
+lock tables t1 write, t2 write, t3 write;
+drop table t2, t3, t1;
+create table t1 (c1 int);
+create table t2 (c1 int);
+create table t3 (c1 int);
+lock tables t1 write, t2 write, t3 write, t1 as t4 read;
+alter table t2 add column c2 int;
+drop table t1, t2, t3;
 create table t1 ( a int(11) not null auto_increment, primary key(a));
 create table t2 ( a int(11) not null auto_increment, primary key(a));
 lock tables t1 write, t2 read;

mysql-test/t/lock.test

@@ -61,6 +61,24 @@ insert into t1 select index1,nr from t1 as t1_alias;
 drop table t1,t2;
 
 #
+# BUG#5390 - problems with merge tables
+# Supplement test for the after-fix optimization
+# Check that a dropped table is correctly removed from a lock.
+create table t1 (c1 int);
+create table t2 (c1 int);
+create table t3 (c1 int);
+lock tables t1 write, t2 write, t3 write;
+# This removes one table after the other from the lock.
+drop table t2, t3, t1;
+#
+# Check that a lock merge works.
+create table t1 (c1 int);
+create table t2 (c1 int);
+create table t3 (c1 int);
+lock tables t1 write, t2 write, t3 write, t1 as t4 read;
+alter table t2 add column c2 int;
+drop table t1, t2, t3;
+
 # Bug7241 - Invalid response when DELETE .. USING and LOCK TABLES used.
 #
 create table t1 ( a int(11) not null auto_increment, primary key(a));

sql/sql_insert.cc

@@ -1536,7 +1536,10 @@ TABLE *delayed_insert::get_local_table(THD* client_thd)
 
   /* Adjust in_use for pointing to client thread */
   copy->in_use= client_thd;
-  
+
+  /* Adjust lock_count. This table object is not part of a lock. */
+  copy->lock_count= 0;
+
   return copy;
 
   /* Got fatal error */

sql/table.h

@@ -236,7 +236,10 @@ struct st_table {
   */
   timestamp_auto_set_type timestamp_field_type;
   table_map	map;                    /* ID bit of table (1,2,4,8,16...) */
-  
+
+  uint          lock_position;          /* Position in MYSQL_LOCK.table */
+  uint          lock_data_start;        /* Start pos. in MYSQL_LOCK.locks */
+  uint          lock_count;             /* Number of locks */
   uint		tablenr,used_fields;
   uint          temp_pool_slot;		/* Used by intern temp tables */
   uint		status;                 /* What's in record[0] */
@@ -245,8 +248,8 @@ struct st_table {
   uint          derived_select_number;
   int		current_lock;           /* Type of lock on table */
   my_bool copy_blobs;			/* copy_blobs when storing */
-  
-  /* 
+
+  /*
     0 or JOIN_TYPE_{LEFT|RIGHT}. Currently this is only compared to 0.
     If maybe_null !=0, this table is inner w.r.t. some outer join operation,
     and null_row may be true.