ndb_lock.test, ndb_lock.result:

  bug #18184  SELECT ... FOR UPDATE does not work..: New test case
ha_ndbcluster.h, ha_ndbcluster.cc, NdbConnection.hpp:
  Fix for bug #21059  Server crashes on join query with large dataset with NDB tables: Releasing operation for each intermediate batch, before next call to trans->execute(NoCommit);

mysql-test/r/ndb_lock.result

@@ -64,17 +64,26 @@ pk	u	o
 insert into t1 values (1,1,1);
 drop table t1;
 create table t1 (x integer not null primary key, y varchar(32), z integer, key(z)) engine = ndb;
-insert into t1 values (1,'one',1), (2,'two',2),(3,"three",3);
+insert into t1 values (1,'one',1);
 begin;
 select * from t1 where x = 1 for update;
 x	y	z
 1	one	1
 begin;
-select * from t1 where x = 2 for update;
+select * from t1 where x = 1 for update;
+ERROR HY000: Lock wait timeout exceeded; try restarting transaction
+rollback;
+rollback;
+insert into t1 values (2,'two',2),(3,"three",3);
+begin;
+select * from t1 where x = 1 for update;
 x	y	z
-2	two	2
+1	one	1
 select * from t1 where x = 1 for update;
 ERROR HY000: Lock wait timeout exceeded; try restarting transaction
+select * from t1 where x = 2 for update;
+x	y	z
+2	two	2
 rollback;
 commit;
 begin;

mysql-test/t/ndb_lock.test

@@ -73,7 +73,7 @@ drop table t1;
 
 create table t1 (x integer not null primary key, y varchar(32), z integer, key(z)) engine = ndb;
 
-insert into t1 values (1,'one',1), (2,'two',2),(3,"three",3); 
+insert into t1 values (1,'one',1);
 
 # PK access
 connection con1;
@@ -82,11 +82,22 @@ select * from t1 where x = 1 for update;
 
 connection con2;
 begin;
-select * from t1 where x = 2 for update;
 --error 1205
 select * from t1 where x = 1 for update;
 rollback;
 
+connection con1;
+rollback;
+insert into t1 values (2,'two',2),(3,"three",3); 
+begin;
+select * from t1 where x = 1 for update;
+
+connection con2;
+--error 1205
+select * from t1 where x = 1 for update;
+select * from t1 where x = 2 for update;
+rollback;
+
 connection con1;
 commit;
 

ndb/include/ndbapi/NdbConnection.hpp

@@ -163,6 +163,7 @@ class NdbConnection
   friend class NdbIndexOperation;
   friend class NdbIndexScanOperation;
   friend class NdbBlob;
+  friend class ha_ndbcluster;
 
 public:
 
@@ -675,6 +676,7 @@ private:
   // optim: any blobs
   bool theBlobFlag;
   Uint8 thePendingBlobOps;
+  inline bool hasBlobOperation() { return theBlobFlag; }
 
   static void sendTC_COMMIT_ACK(NdbApiSignal *,
 				Uint32 transId1, Uint32 transId2, 

sql/ha_ndbcluster.cc

@@ -161,6 +161,7 @@ int execute_no_commit(ha_ndbcluster *h, NdbConnection *trans)
   if (m_batch_execute)
     return 0;
 #endif
+  h->release_completed_operations(trans);
   return trans->execute(NoCommit,AbortOnError,h->m_force_send);
 }
 
@@ -194,6 +195,7 @@ int execute_no_commit_ie(ha_ndbcluster *h, NdbConnection *trans)
   if (m_batch_execute)
     return 0;
 #endif
+  h->release_completed_operations(trans);
   return trans->execute(NoCommit, AO_IgnoreError,h->m_force_send);
 }
 
@@ -2747,6 +2749,25 @@ int ha_ndbcluster::close_scan()
   if (!cursor)
     DBUG_RETURN(1);
 
+  if (m_lock_tuple)
+  {
+    /*
+      Lock level m_lock.type either TL_WRITE_ALLOW_WRITE
+      (SELECT FOR UPDATE) or TL_READ_WITH_SHARED_LOCKS (SELECT
+      LOCK WITH SHARE MODE) and row was not explictly unlocked 
+      with unlock_row() call
+    */
+      NdbOperation *op;
+      // Lock row
+      DBUG_PRINT("info", ("Keeping lock on scanned row"));
+      
+      if (!(op= m_active_cursor->lockTuple()))
+      {
+	m_lock_tuple= false;
+	ERR_RETURN(trans->getNdbError());
+      }
+      m_ops_pending++;      
+  }
   m_lock_tuple= false;
   if (m_ops_pending)
   {
@@ -5350,6 +5371,19 @@ int ha_ndbcluster::write_ndb_file()
   DBUG_RETURN(error);
 }
 
+void 
+ha_ndbcluster::release_completed_operations(NdbConnection *trans)
+{
+  if (trans->hasBlobOperation())
+  {
+    /* We are reading/writing BLOB fields, 
+       releasing operation records is unsafe
+    */
+    return;
+  }
+  trans->releaseCompletedOperations();
+}
+
 int
 ndbcluster_show_status(THD* thd)
 {

sql/ha_ndbcluster.h

@@ -262,6 +262,8 @@ class ha_ndbcluster: public handler
   void no_uncommitted_rows_init(THD *);
   void no_uncommitted_rows_reset(THD *);
 
+  void release_completed_operations(NdbConnection*);
+
   friend int execute_no_commit(ha_ndbcluster*, NdbConnection*);
   friend int execute_commit(ha_ndbcluster*, NdbConnection*);
   friend int execute_no_commit_ie(ha_ndbcluster*, NdbConnection*);