Bug #27123 (partition + on duplicate key update + varchar = Can't find

record in table)

key_restore function didn't work as intended in the case of
VARCHAR or BLOB fields, stored the restored key in field->ptr instead
of to_record.
That produced the wrong key so search returned wrong result


mysql-test/r/partition.result:
  result added
mysql-test/t/partition.test:
  testcase
sql/field.cc:
  Field_blob::store_length made static
sql/field.h:
  Field_blob::store_length and set_ptr functions implemented in slightly
  different way
sql/ha_ndbcluster.cc:
  set_ptr_offset used
sql/key.cc:
  set key_part->field->ptr to the proper place inside the to_record
  so the restored key will be placed there as key_restore
  is supposed to behave

6 files changed, 53 insertions, 16 deletions

diff --git a/mysql-test/r/partition.result b/mysql-test/r/partition.result
index 2e5fa4b9195..46b704dc7b7 100644
--- a/mysql-test/r/partition.result
+++ b/mysql-test/r/partition.result
@@ -1238,4 +1238,12 @@ t2	CREATE TABLE `t2` (
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1 /*!50100 PARTITION BY RANGE (i) (PARTITION p01 VALUES LESS THAN (1000) ENGINE = MyISAM) */
 DROP TABLE t1, t2;
 set @@sql_mode=@org_mode;
+create table t1 (c1 varchar(255),c2 tinyint,primary key(c1))
+partition by key (c1) partitions 10 ;
+insert into t1 values ('aaa','1') on duplicate key update c2 = c2 + 1;
+insert into t1 values ('aaa','1') on duplicate key update c2 = c2 + 1;
+select * from t1;
+c1	c2
+aaa	2
+drop table t1;
 End of 5.1 tests
diff --git a/mysql-test/t/partition.test b/mysql-test/t/partition.test
index 399f3c4a41d..d6421b0ca3d 100644
--- a/mysql-test/t/partition.test
+++ b/mysql-test/t/partition.test
@@ -1492,4 +1492,15 @@ show create table t2;
 DROP TABLE t1, t2;
 set @@sql_mode=@org_mode;
 
+#
+# Bug #27123 partition + on duplicate key update + varchar = Can't find record in <table> 
+#
+create table t1 (c1 varchar(255),c2 tinyint,primary key(c1))
+   partition by key (c1) partitions 10 ;
+insert into t1 values ('aaa','1') on duplicate key update c2 = c2 + 1;
+insert into t1 values ('aaa','1') on duplicate key update c2 = c2 + 1;
+select * from t1;
+drop table t1;
+
+
 --echo End of 5.1 tests
diff --git a/sql/field.cc b/sql/field.cc
index a48a3ff7bcd..240c48bdf0c 100644
--- a/sql/field.cc
+++ b/sql/field.cc
@@ -6969,7 +6969,7 @@ Field_blob::Field_blob(char *ptr_arg, uchar *null_ptr_arg, uchar null_bit_arg,
 }
 
 
-void Field_blob::store_length(uint32 number)
+void Field_blob::store_length(char *ptr, uint packlength, uint32 number)
 {
   switch (packlength) {
   case 1:
diff --git a/sql/field.h b/sql/field.h
index 3d1ac7528c1..ac26ce13477 100644
--- a/sql/field.h
+++ b/sql/field.h
@@ -1274,7 +1274,12 @@ public:
   }
   int reset(void) { bzero(ptr, packlength+sizeof(char*)); return 0; }
   void reset_fields() { bzero((char*) &value,sizeof(value)); }
-  void store_length(uint32 number);
+  static void store_length(char *ptr, uint packlength, uint32 number);
+  inline void store_length(uint32 number)
+  {
+    store_length(ptr, packlength, number);
+  }
+
   inline uint32 get_length(uint row_offset=0)
   { return get_length(ptr+row_offset); }
   uint32 get_length(const char *ptr);
@@ -1292,11 +1297,17 @@ public:
       memcpy(ptr,length,packlength);
       memcpy_fixed(ptr+packlength,&data,sizeof(char*));
     }
+  void set_ptr_offset(my_ptrdiff_t ptr_diff, uint32 length,char *data)
+    {
+      char *ptr_ofs= ADD_TO_PTR(ptr,ptr_diff,char*);
+      store_length(ptr_ofs, packlength, length);
+      memcpy_fixed(ptr_ofs+packlength,&data,sizeof(char*));
+    }
   inline void set_ptr(uint32 length,char *data)
     {
-      store_length(length);
-      memcpy_fixed(ptr+packlength,&data,sizeof(char*));
+      set_ptr_offset(0, length, data);
     }
+
   void get_key_image(char *buff,uint length, imagetype type);
   void set_key_image(char *buff,uint length);
   void sql_type(String &str) const;
diff --git a/sql/ha_ndbcluster.cc b/sql/ha_ndbcluster.cc
index 5a0f27073d4..5f5e4d3ed51 100644
--- a/sql/ha_ndbcluster.cc
+++ b/sql/ha_ndbcluster.cc
@@ -853,9 +853,7 @@ int get_ndb_blobs_value(TABLE* table, NdbValue* value_array,
                               i, offset, (long) buf, len, (int)ptrdiff));
           DBUG_ASSERT(len == len64);
           // Ugly hack assumes only ptr needs to be changed
-          field_blob->ptr+= ptrdiff;
-          field_blob->set_ptr(len, buf);
-          field_blob->ptr-= ptrdiff;
+          field_blob->set_ptr_offset(ptrdiff, len, buf);
         }
         offset+= size;
       }
@@ -864,9 +862,7 @@ int get_ndb_blobs_value(TABLE* table, NdbValue* value_array,
         // have to set length even in this case
         char *buf= buffer + offset; // or maybe NULL
         uint32 len= 0;
-        field_blob->ptr+= ptrdiff;
-        field_blob->set_ptr(len, buf);
-        field_blob->ptr-= ptrdiff;
+        field_blob->set_ptr_offset(ptrdiff, len, buf);
         DBUG_PRINT("info", ("[%u] isNull=%d", i, isNull));
       }
     }
diff --git a/sql/key.cc b/sql/key.cc
index faa7bf1f04b..5054998bd99 100644
--- a/sql/key.cc
+++ b/sql/key.cc
@@ -221,23 +221,34 @@ void key_restore(byte *to_record, byte *from_key, KEY *key_info,
     }
     if (key_part->key_part_flag & HA_BLOB_PART)
     {
+      /*
+        This in fact never happens, as we have only partial BLOB
+        keys yet anyway, so it's difficult to find any sence to
+        restore the part of a record.
+        Maybe this branch is to be removed, but now we
+        have to ignore GCov compaining.
+      */
       uint blob_length= uint2korr(from_key);
+      Field_blob *field= (Field_blob*) key_part->field;
       from_key+= HA_KEY_BLOB_LENGTH;
       key_length-= HA_KEY_BLOB_LENGTH;
-      ((Field_blob*) key_part->field)->set_ptr((ulong) blob_length,
-					       (char*) from_key);
+      field->set_ptr_offset(to_record - field->table->record[0],
+                            (ulong) blob_length, (char*) from_key);
       length= key_part->length;
     }
     else if (key_part->key_part_flag & HA_VAR_LENGTH_PART)
     {
+      Field *field= key_part->field;
       my_bitmap_map *old_map;
+      my_ptrdiff_t ptrdiff= to_record - field->table->record[0];
+      field->move_field_offset(ptrdiff);
       key_length-= HA_KEY_BLOB_LENGTH;
       length= min(key_length, key_part->length);
-      old_map= dbug_tmp_use_all_columns(key_part->field->table,
-                                        key_part->field->table->write_set);
-      key_part->field->set_key_image((char *) from_key, length);
-      dbug_tmp_restore_column_map(key_part->field->table->write_set, old_map);
+      old_map= dbug_tmp_use_all_columns(field->table, field->table->write_set);
+      field->set_key_image((char *) from_key, length);
+      dbug_tmp_restore_column_map(field->table->write_set, old_map);
       from_key+= HA_KEY_BLOB_LENGTH;
+      field->move_field_offset(-ptrdiff);
     }
     else
     {