diff --git a/mysql-test/r/insert_select.result b/mysql-test/r/insert_select.result
index 94d33f8090b..8882b95f2d8 100644
--- a/mysql-test/r/insert_select.result
+++ b/mysql-test/r/insert_select.result
@@ -638,3 +638,15 @@ No	Field	Count
 0	1	100
 0	2	100
 drop table t1, t2;
+CREATE TABLE t1 (
+ID           int(11) NOT NULL auto_increment,
+NO           int(11) NOT NULL default '0',
+SEQ          int(11) NOT NULL default '0',
+PRIMARY KEY  (ID),
+KEY t1$NO    (SEQ,NO)
+) ENGINE=MyISAM;
+INSERT INTO t1 (SEQ, NO) SELECT "1" AS SEQ, IF(MAX(NO) IS NULL, 0, MAX(NO)) + 1 AS NO FROM t1 WHERE (SEQ = 1);
+select SQL_BUFFER_RESULT * from t1 WHERE (SEQ = 1);
+ID	NO	SEQ
+1	1	1
+drop table t1;
diff --git a/mysql-test/t/insert_select.test b/mysql-test/t/insert_select.test
index 15509b06679..a5b163b3533 100644
--- a/mysql-test/t/insert_select.test
+++ b/mysql-test/t/insert_select.test
@@ -180,3 +180,18 @@ insert into t2 Select null, Field, Count From t1 Where Month=20030901 and Type=2
 select * from t2;
 
 drop table t1, t2;
+
+#
+# BUG#6034 - Error code 124:  Wrong medium type
+#
+CREATE TABLE t1 (
+  ID           int(11) NOT NULL auto_increment,
+  NO           int(11) NOT NULL default '0',
+  SEQ          int(11) NOT NULL default '0',
+  PRIMARY KEY  (ID),
+  KEY t1$NO    (SEQ,NO)
+) ENGINE=MyISAM;
+INSERT INTO t1 (SEQ, NO) SELECT "1" AS SEQ, IF(MAX(NO) IS NULL, 0, MAX(NO)) + 1 AS NO FROM t1 WHERE (SEQ = 1);
+select SQL_BUFFER_RESULT * from t1 WHERE (SEQ = 1);
+drop table t1;
+
diff --git a/sql/sql_class.h b/sql/sql_class.h
index ca65f011b9d..8e6204ab3a3 100644
--- a/sql/sql_class.h
+++ b/sql/sql_class.h
@@ -1280,6 +1280,7 @@ public:
     unit= u;
     return 0;
   }
+  virtual int prepare2(void) { return 0; }
   /*
     Because of peculiarities of prepared statements protocol
     we need to know number of columns in the result set (if
@@ -1379,6 +1380,7 @@ class select_insert :public select_result_interceptor {
 		enum_duplicates duplic, bool ignore);
   ~select_insert();
   int prepare(List<Item> &list, SELECT_LEX_UNIT *u);
+  int prepare2(void);
   bool send_data(List<Item> &items);
   virtual void store_values(List<Item> &values);
   void send_error(uint errcode,const char *err);
diff --git a/sql/sql_insert.cc b/sql/sql_insert.cc
index ceb31f76953..4cb62d5e9d7 100644
--- a/sql/sql_insert.cc
+++ b/sql/sql_insert.cc
@@ -1802,13 +1802,22 @@ select_insert::prepare(List<Item> &values, SELECT_LEX_UNIT *u)
     thd->lex->current_select->options|= OPTION_BUFFER_RESULT;
     thd->lex->current_select->join->select_options|= OPTION_BUFFER_RESULT;
   }
-
+  else
+  {
+    /*
+      We must not yet prepare the result table if it is the same as one of the 
+      source tables (INSERT SELECT). The preparation may disable 
+      indexes on the result table, which may be used during the select, if it
+      is the same table (Bug #6034). Do the preparation after the select phase
+      in select_insert::prepare2().
+    */
+    if (info.ignore || info.handle_duplicates != DUP_ERROR)
+      table->file->extra(HA_EXTRA_IGNORE_DUP_KEY);
+    table->file->start_bulk_insert((ha_rows) 0);
+  }
   restore_record(table,s->default_values);		// Get empty record
   table->next_number_field=table->found_next_number_field;
   thd->cuted_fields=0;
-  if (info.ignore || info.handle_duplicates != DUP_ERROR)
-    table->file->extra(HA_EXTRA_IGNORE_DUP_KEY);
-  table->file->start_bulk_insert((ha_rows) 0);
   thd->no_trans_update= 0;
   thd->abort_on_warning= (!info.ignore &&
                           (thd->variables.sql_mode &
@@ -1819,6 +1828,36 @@ select_insert::prepare(List<Item> &values, SELECT_LEX_UNIT *u)
 }
 
 
+/*
+  Finish the preparation of the result table.
+
+  SYNOPSIS
+    select_insert::prepare2()
+    void
+
+  DESCRIPTION
+    If the result table is the same as one of the source tables (INSERT SELECT),
+    the result table is not finally prepared at the join prepair phase.
+    Do the final preparation now.
+		       
+  RETURN
+    0   OK
+*/
+
+int select_insert::prepare2(void)
+{
+  DBUG_ENTER("select_insert::prepare2");
+
+  if (thd->lex->current_select->options & OPTION_BUFFER_RESULT)
+  {
+    if (info.ignore || info.handle_duplicates != DUP_ERROR)
+      table->file->extra(HA_EXTRA_IGNORE_DUP_KEY);
+    table->file->start_bulk_insert((ha_rows) 0);
+  }
+  return 0;
+}
+
+
 void select_insert::cleanup()
 {
   /* select_insert/select_create are never re-used in prepared statement */
diff --git a/sql/sql_select.cc b/sql/sql_select.cc
index 94a2390324c..0fc4616749c 100644
--- a/sql/sql_select.cc
+++ b/sql/sql_select.cc
@@ -1164,6 +1164,7 @@ JOIN::exec()
       DBUG_VOID_RETURN;
     }
   }
+  (void) result->prepare2(); // Currently, this cannot fail.
 
   if (!tables_list)
   {                                           // Only test of functions
@@ -13149,7 +13150,8 @@ bool JOIN::change_result(select_result *res)
 {
   DBUG_ENTER("JOIN::change_result");
   result= res;
-  if (!procedure && result->prepare(fields_list, select_lex->master_unit()))
+  if (!procedure && (result->prepare(fields_list, select_lex->master_unit()) ||
+                     result->prepare2()))
   {
     DBUG_RETURN(TRUE);
   }