Bug#35027961 ClusterJ hint for single character column partition key is wrong

Remove optimization for single column partitioning key since that did
not work correctly for character columns.

Change-Id: I4eff7ddef0262e3a801289649f65a3cf1f355d32

Author: zmur

storage/ndb/clusterj/clusterj-tie/src/main/java/com/mysql/clusterj/tie/DbImpl.java

@@ -1,5 +1,5 @@
 /*
- *  Copyright (c) 2010, 2021, Oracle and/or its affiliates.
+ *  Copyright (c) 2010, 2023, Oracle and/or its affiliates.
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License, version 2.0,
@@ -257,20 +257,6 @@ public NdbTransaction enlist(String tableName, List<KeyPart> keyParts) {
         TableConst table = ndbDictionary.getTable(tableName);
         handleError(table, ndbDictionary);
         Key_part_ptrArray key_part_ptrArray = null;
-        if (keyPartsSize == 1) {
-            // extract the ByteBuffer and length from the keyPart
-            KeyPart keyPart = keyParts.get(0);
-            ByteBuffer buffer = keyPart.buffer;
-            int length = keyPart.length;
-            ndbTransaction = ndb.startTransaction(table, buffer, length);
-            if (ndbTransaction == null) {
-                logger.warn(local.message("ERR_Transaction_Start_Failed",
-                        tableName, buffer.position(), buffer.limit(), buffer.capacity(), length));
-            }
-            bufferManager.returnPartitionKeyPartBuffer(length, buffer);
-            handleError (ndbTransaction, ndb);
-            return ndbTransaction;
-        }
         key_part_ptrArray = Key_part_ptrArray.create(keyPartsSize + 1);
         try {
             // the key part pointer array has one entry for each key part

storage/ndb/include/ndbapi/Ndb.hpp

@@ -1,5 +1,5 @@
 /*
-   Copyright (c) 2003, 2021, Oracle and/or its affiliates.
+   Copyright (c) 2003, 2023, Oracle and/or its affiliates.
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License, version 2.0,
@@ -1552,7 +1552,12 @@ class Ndb
    *       The transaction must be closed independent of its outcome, i.e.
    *       even if there is an error.
    *
-   * @param  table    Pointer to table object used for deciding 
+   * @note Hinting TC-selection by passing key data only works if key only
+   *       consists of 4-byte aligned values and not using character columns.
+   *       No failure will be returned if that is not the case, rather use the
+   *       startTransaction function that takes Key_part_ptr.
+   *
+   * @param  table    Pointer to table object used for deciding
    *                  which node to run the Transaction Coordinator on
    * @param  keyData  Pointer to partition key corresponding to
    *                  <var>table</var>