Fix for Bug #9691 UPDATE fails on attempt to update primary key

mysql-test/r/ndb_update.result

@@ -2,12 +2,32 @@ DROP TABLE IF EXISTS t1;
 CREATE TABLE t1 (
 pk1 INT NOT NULL PRIMARY KEY,
 b INT NOT NULL,
-c INT NOT NULL
+c INT NOT NULL UNIQUE
 ) ENGINE=ndbcluster;
-INSERT INTO t1 VALUES (0, 0, 1),(1,1,2),(2,2,3);
+INSERT INTO t1 VALUES (0, 1, 0),(1,2,1),(2,3,2);
 UPDATE t1 set b = c;
 select * from t1 order by pk1;
 pk1	b	c
-0	1	1
-1	2	2
-2	3	3
+0	0	0
+1	1	1
+2	2	2
+UPDATE t1 set pk1 = 4 where pk1 = 1;
+select * from t1 order by pk1;
+pk1	b	c
+0	0	0
+2	2	2
+4	1	1
+UPDATE t1 set pk1 = 1, c = 2 where pk1 = 4;
+ERROR 23000: Duplicate entry '1' for key 1
+select * from t1 order by pk1;
+pk1	b	c
+0	0	0
+2	2	2
+4	1	1
+UPDATE t1 set pk1 = pk1 + 10;
+select * from t1 order by pk1;
+pk1	b	c
+10	0	0
+12	2	2
+14	1	1
+DROP TABLE IF EXISTS t1;

mysql-test/t/ndb_update.test

@@ -14,9 +14,20 @@ DROP TABLE IF EXISTS t1;
 CREATE TABLE t1 (
   pk1 INT NOT NULL PRIMARY KEY,
   b INT NOT NULL,
-  c INT NOT NULL
+  c INT NOT NULL UNIQUE
 ) ENGINE=ndbcluster;
 
-INSERT INTO t1 VALUES (0, 0, 1),(1,1,2),(2,2,3);
+INSERT INTO t1 VALUES (0, 1, 0),(1,2,1),(2,3,2);
 UPDATE t1 set b = c;
 select * from t1 order by pk1;
+UPDATE t1 set pk1 = 4 where pk1 = 1;
+select * from t1 order by pk1;
+-- error 1062
+UPDATE t1 set pk1 = 1, c = 2 where pk1 = 4;
+select * from t1 order by pk1;
+UPDATE t1 set pk1 = pk1 + 10;
+select * from t1 order by pk1;
+
+--disable_warnings
+DROP TABLE IF EXISTS t1;
+--enable_warnings

sql/ha_ndbcluster.cc

@@ -1863,7 +1863,9 @@ int ha_ndbcluster::write_row(byte *record)
       m_skip_auto_increment= !auto_increment_column_changed;
     }
 
-    if ((res= set_primary_key(op)))
+    if ((res= (m_primary_key_update ?
+               set_primary_key_from_old_data(op, record)
+               : set_primary_key(op))))
       return res;  
   }
 
@@ -2001,7 +2003,7 @@ int ha_ndbcluster::update_row(const byte *old_data, byte *new_data)
   {
     int read_res, insert_res, delete_res;
 
-    DBUG_PRINT("info", ("primary key update, doing pk read+insert+delete"));
+    DBUG_PRINT("info", ("primary key update, doing pk read+delete+insert"));
     // Get all old fields, since we optimize away fields not in query
     read_res= complemented_pk_read(old_data, new_data);
     if (read_res)
@@ -2009,15 +2011,7 @@ int ha_ndbcluster::update_row(const byte *old_data, byte *new_data)
       DBUG_PRINT("info", ("pk read failed"));
       DBUG_RETURN(read_res);
     }
-    // Insert new row
-    insert_res= write_row(new_data);
-    if (insert_res)
-    {
-      DBUG_PRINT("info", ("insert failed"));
-      DBUG_RETURN(insert_res);
-    }
     // Delete old row
-    DBUG_PRINT("info", ("insert succeded"));
     m_primary_key_update= TRUE;
     delete_res= delete_row(old_data);
     m_primary_key_update= FALSE;
@@ -2025,9 +2019,23 @@ int ha_ndbcluster::update_row(const byte *old_data, byte *new_data)
     {
       DBUG_PRINT("info", ("delete failed"));
       // Undo write_row(new_data)
-      DBUG_RETURN(delete_row(new_data));
+      DBUG_RETURN(delete_res);
+    }     
+    // Insert new row
+    DBUG_PRINT("info", ("delete succeded"));
+    insert_res= write_row(new_data);
+    if (insert_res)
+    {
+      DBUG_PRINT("info", ("insert failed"));
+      if (trans->commitStatus() == NdbConnection::Started)
+      {
+        m_primary_key_update= TRUE;
+        insert_res= write_row((byte *)old_data);
+        m_primary_key_update= FALSE;
+      }
+      DBUG_RETURN(insert_res);
     }
-    DBUG_PRINT("info", ("insert+delete succeeded"));
+    DBUG_PRINT("info", ("delete+insert succeeded"));
     DBUG_RETURN(0);
   }
 
@@ -2125,6 +2133,7 @@ int ha_ndbcluster::delete_row(const byte *record)
 
     no_uncommitted_rows_update(-1);
 
+    if (!m_primary_key_update)
       // If deleting from cursor, NoCommit will be handled in next_result
       DBUG_RETURN(0);
   }