Merge spetrunia@bk-internal.mysql.com:/home/bk/mysql-4.0

into mysql.com:/dbdata/psergey/mysql-4.0-root

mysql-test/r/handler.result

@@ -191,3 +191,15 @@ Ok
 handler t close;
 use test;
 drop table t1;
+create table t1 ( a int, b int, INDEX a (a) );
+insert into t1 values (1,2), (2,1);
+handler t1 open;
+handler t1 read a=(1) where b=2;
+a	b
+1	2
+handler t1 read a=(1) where b=3;
+a	b
+handler t1 read a=(1) where b=1;
+a	b
+handler t1 close;
+drop table t1;

mysql-test/t/handler.test

@@ -123,3 +123,15 @@ handler t close;
 use test;
 drop table t1;
 
+#
+# BUG#3649
+#
+create table t1 ( a int, b int, INDEX a (a) );
+insert into t1 values (1,2), (2,1);
+handler t1 open;
+handler t1 read a=(1) where b=2;
+handler t1 read a=(1) where b=3;
+handler t1 read a=(1) where b=1;
+handler t1 close;
+drop table t1;
+

sql/sql_class.h

@@ -28,7 +28,7 @@ class Load_log_event;
 class Slave_log_event;
 
 enum enum_enable_or_disable { LEAVE_AS_IS, ENABLE, DISABLE };
-enum enum_ha_read_modes { RFIRST, RNEXT, RPREV, RLAST, RKEY };
+enum enum_ha_read_modes { RFIRST, RNEXT, RPREV, RLAST, RKEY, RNEXT_SAME };
 enum enum_duplicates { DUP_ERROR, DUP_REPLACE, DUP_IGNORE };
 enum enum_log_type { LOG_CLOSED, LOG_TO_BE_OPENED, LOG_NORMAL, LOG_NEW, LOG_BIN};
 enum enum_delay_key_write { DELAY_KEY_WRITE_NONE, DELAY_KEY_WRITE_ON,

sql/sql_handler.cc

@@ -103,7 +103,7 @@ int mysql_ha_closeall(THD *thd, TABLE_LIST *tables)
 }
 
 static enum enum_ha_read_modes rkey_to_rnext[]=
-    { RNEXT, RNEXT, RPREV, RNEXT, RPREV, RNEXT, RPREV };
+    { RNEXT_SAME, RNEXT, RPREV, RNEXT, RPREV, RNEXT, RPREV };
 
 
 int mysql_ha_read(THD *thd, TABLE_LIST *tables,
@@ -151,6 +151,11 @@ int mysql_ha_read(THD *thd, TABLE_LIST *tables,
   HANDLER_TABLES_HACK(thd);
   MYSQL_LOCK *lock=mysql_lock_tables(thd,&tables->table,1);
   HANDLER_TABLES_HACK(thd);
+  
+  byte *key;
+  uint key_len;
+  LINT_INIT(key); 
+  LINT_INIT(key_len); 
   if (!lock)
      goto err0; // mysql_lock_tables() printed error message already
 
@@ -183,13 +188,16 @@ int mysql_ha_read(THD *thd, TABLE_LIST *tables,
       DBUG_ASSERT(keyname != 0);
       err=table->file->index_prev(table->record[0]);
       break;
+    case RNEXT_SAME:
+      /* Continue scan on "(keypart1,keypart2,...)=(c1, c2, ...)  */
+      DBUG_ASSERT(keyname != 0);
+      err= table->file->index_next_same(table->record[0], key, key_len);
+      break;
     case RKEY:
     {
       DBUG_ASSERT(keyname != 0);
       KEY *keyinfo=table->key_info+keyno;
       KEY_PART_INFO *key_part=keyinfo->key_part;
-      uint key_len;
-      byte *key;
       if (key_expr->elements > keyinfo->key_parts)
       {
         my_printf_error(ER_TOO_MANY_KEY_PARTS,ER(ER_TOO_MANY_KEY_PARTS),