Merge fix for BUG51307 to 5.1-bugteam.

mysql-test/r/myisam.result

@@ -2356,4 +2356,37 @@ CHECKSUM TABLE t3 EXTENDED;
 Table	Checksum
 test.t3	3775188275
 DROP TABLE t1, t2, t3;
+#
+# BUG#51307 - widespread corruption with partitions and insert...select
+#
+CREATE TABLE t1(a CHAR(255), KEY(a));
+SELECT * FROM t1, t1 AS a1;
+a	a
+SET myisam_sort_buffer_size=4;
+INSERT INTO t1 VALUES
+('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),
+('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),
+('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),
+('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),
+('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),
+('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),
+('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),
+('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),
+('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),
+('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),
+('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),
+('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),
+('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),
+('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),
+('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),
+('0'),('0'),('0'),('0'),('0'),('0'),('0');
+Warnings:
+Error	1034	myisam_sort_buffer_size is too small
+Error	1034	Number of rows changed from 0 to 157
+SET myisam_sort_buffer_size=@@global.myisam_sort_buffer_size;
+INSERT INTO t1 VALUES('1');
+SELECT * FROM t1, t1 AS a1 WHERE t1.a=1 AND a1.a=1;
+a	a
+1	1
+DROP TABLE t1;
 End of 5.1 tests

mysql-test/t/myisam.test

@@ -1603,4 +1603,32 @@ CHECKSUM TABLE t2 EXTENDED;
 CHECKSUM TABLE t3 EXTENDED;
 DROP TABLE t1, t2, t3;
 
+--echo #
+--echo # BUG#51307 - widespread corruption with partitions and insert...select
+--echo #
+CREATE TABLE t1(a CHAR(255), KEY(a));
+SELECT * FROM t1, t1 AS a1;
+SET myisam_sort_buffer_size=4;
+INSERT INTO t1 VALUES
+('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),
+('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),
+('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),
+('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),
+('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),
+('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),
+('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),
+('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),
+('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),
+('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),
+('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),
+('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),
+('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),
+('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),
+('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),('0'),
+('0'),('0'),('0'),('0'),('0'),('0'),('0');
+SET myisam_sort_buffer_size=@@global.myisam_sort_buffer_size;
+INSERT INTO t1 VALUES('1');
+SELECT * FROM t1, t1 AS a1 WHERE t1.a=1 AND a1.a=1;
+DROP TABLE t1;
+
 --echo End of 5.1 tests

storage/myisam/ha_myisam.cc

@@ -1448,9 +1448,17 @@ int ha_myisam::enable_indexes(uint mode)
     {
       sql_print_warning("Warning: Enabling keys got errno %d on %s.%s, retrying",
                         my_errno, param.db_name, param.table_name);
-      /* Repairing by sort failed. Now try standard repair method. */
-      param.testflag&= ~(T_REP_BY_SORT | T_QUICK);
+      /*
+        Repairing by sort failed. Now try standard repair method.
+        Still we want to fix only index file. If data file corruption
+        was detected (T_RETRY_WITHOUT_QUICK), we shouldn't do much here.
+        Let implicit repair do this job.
+      */
+      if (!(param.testflag & T_RETRY_WITHOUT_QUICK))
+      {
+        param.testflag&= ~T_REP_BY_SORT;
         error= (repair(thd,param,0) != HA_ADMIN_OK);
+      }
       /*
         If the standard repair succeeded, clear all error messages which
         might have been set by the first repair. They can still be seen