Moved reading of ranges from opt_range.cc to handler.cc

This gives the handler more optimization possiblities and is needed for NDB cluster
Fixed not-initialized memory error detected by valgrind


mysql-test/mysql-test-run.sh:
  Fixed address to manual page
mysql-test/r/gis-rtree.result:
  Added test to show fatal error in GIS
mysql-test/r/grant.result:
  New tests
mysql-test/t/gis-rtree.test:
  New tests
mysql-test/t/grant.test:
  New tests
sql/handler.cc:
  Moved reading of ranges from opt_range.cc to handler.cc
  This gives the handler more optimization possiblities and is needed for NDB cluster
sql/handler.h:
  Moved reading of ranges from opt_range.cc to handler.cc
  T
sql/opt_range.cc:
  Moved reading of ranges from opt_range.cc to handler.cc
  Simplified GIS get_next() handling
  Indentation cleanups
sql/opt_range.h:
  Removed not needed cmp_next()
  Added new QUICK_SELECT method for GIS keys to make code for normal keys easier and faster
sql/sql_select.cc:
  Fixed wrong handling of usable-keys in test_if_skip_sort_order (not fatal, just a warning from valgrind)
  Added DBUG
  Cleaned up comments

mysql-test/mysql-test-run.sh

@@ -670,7 +670,7 @@ report_stats () {
         $ECHO "The log files in $MY_LOG_DIR may give you some hint"
 	$ECHO "of what when wrong."
 	$ECHO "If you want to report this error, please read first the documentation at"
-        $ECHO "http://www.mysql.com/doc/M/y/MySQL_test_suite.html"
+        $ECHO "http://www.mysql.com/doc/en/MySQL_test_suite.html"
     fi
 
     if test -z "$USE_RUNNING_SERVER"

mysql-test/r/gis-rtree.result

@@ -750,3 +750,10 @@ analyze table t1;
 Table	Op	Msg_type	Msg_text
 test.t1	analyze	status	OK
 drop table t1;
+CREATE TABLE t1 (
+fid INT NOT NULL AUTO_INCREMENT PRIMARY KEY, 
+g GEOMETRY NOT NULL,
+SPATIAL KEY(g)
+) ENGINE=MyISAM;
+INSERT INTO t1 (g) VALUES (GeomFromText('LineString(1 2, 2 3)')),(GeomFromText('LineString(1 2, 2 4)'));
+drop table t1;

mysql-test/r/grant.result

@@ -76,6 +76,8 @@ delete from mysql.db where user='mysqltest_1';
 delete from mysql.tables_priv where user='mysqltest_1';
 delete from mysql.columns_priv where user='mysqltest_1';
 flush privileges;
+show grants for mysqltest_1@localhost;
+ERROR 42000: There is no such grant defined for user 'mysqltest_1' on host 'localhost'
 create table t1 (a int);
 GRANT select,update,insert on t1 to mysqltest_1@localhost;
 GRANT select (a), update (a),insert(a), references(a) on t1 to mysqltest_1@localhost;

mysql-test/t/gis-rtree.test

@@ -103,3 +103,16 @@ check table t1;
 analyze table t1;
 drop table t1;
 
+#
+# The following crashed gis
+#
+
+CREATE TABLE t1 (
+  fid INT NOT NULL AUTO_INCREMENT PRIMARY KEY, 
+  g GEOMETRY NOT NULL,
+  SPATIAL KEY(g)
+) ENGINE=MyISAM;
+
+INSERT INTO t1 (g) VALUES (GeomFromText('LineString(1 2, 2 3)')),(GeomFromText('LineString(1 2, 2 4)'));
+#select * from t1 where g<GeomFromText('LineString(1 2, 2 3)');
+drop table t1;

mysql-test/t/grant.test

@@ -53,6 +53,8 @@ delete from mysql.db where user='mysqltest_1';
 delete from mysql.tables_priv where user='mysqltest_1';
 delete from mysql.columns_priv where user='mysqltest_1';
 flush privileges;
+--error 1141
+show grants for mysqltest_1@localhost;
 
 #
 # Test what happens when you have same table and colum level grants

sql/handler.cc

@@ -1287,3 +1287,141 @@ int ha_change_key_cache(KEY_CACHE *old_key_cache,
   mi_change_key_cache(old_key_cache, new_key_cache);
   return 0;
 }
+
+
+/*
+  Read first row between two ranges.
+  Store ranges for future calls to read_range_next
+
+  SYNOPSIS
+    read_range_first()
+    start_key		Start key. Is 0 if no min range
+    end_key		End key.  Is 0 if no max range
+    sorted		Set to 1 if result should be sorted per key
+
+  NOTES
+    Record is read into table->record[0]
+
+  RETURN
+    0			Found row
+    HA_ERR_END_OF_FILE	No rows in range
+    #			Error code
+*/
+
+int handler::read_range_first(const key_range *start_key,
+			      const key_range *end_key,
+			      bool sorted)
+{
+  int result;
+  DBUG_ENTER("handler::read_range_first");
+
+  end_range= 0;
+  if (end_key)
+  {
+    end_range= &save_end_range;
+    save_end_range= *end_key;
+    key_compare_result_on_equal= ((end_key->flag == HA_READ_BEFORE_KEY) ? 1 :
+				  (end_key->flag == HA_READ_AFTER_KEY) ? -1 : 0);
+  }
+  range_key_part= table->key_info[active_index].key_part;
+
+
+  if (!start_key)			// Read first record
+    result= index_first(table->record[0]);
+  else
+    result= index_read(table->record[0],
+		       start_key->key,
+		       start_key->length,
+		       start_key->flag);
+  if (result)
+    DBUG_RETURN((result == HA_ERR_KEY_NOT_FOUND ||
+		 result == HA_ERR_END_OF_FILE) ? HA_ERR_END_OF_FILE :
+		result);
+
+  DBUG_RETURN (compare_key(end_range) <= 0 ? 0 : HA_ERR_END_OF_FILE);
+}
+
+
+/*
+  Read next row between two ranges.
+
+  SYNOPSIS
+    read_range_next()
+    eq_range		Set to 1 if start_key == end_key
+
+  NOTES
+    Record is read into table->record[0]
+
+  RETURN
+    0			Found row
+    HA_ERR_END_OF_FILE	No rows in range
+    #			Error code
+*/
+
+int handler::read_range_next(bool eq_range)
+{
+  int result;
+  DBUG_ENTER("handler::read_range_next");
+
+  if (eq_range)
+    result= index_next_same(table->record[0],
+			    end_range->key,
+			    end_range->length);
+  else
+    result= index_next(table->record[0]);
+  if (result)
+    DBUG_RETURN(result);
+  DBUG_RETURN(compare_key(end_range) <= 0 ? 0 : HA_ERR_END_OF_FILE);
+}
+
+
+/*
+  Compare if found key is over max-value
+
+  SYNOPSIS
+    compare_key
+    range		key to compare to row
+ 
+  NOTES
+    For this to work, the row must be stored in table->record[0]
+
+  RETURN
+    0			Key is equal to range or 'range' == 0 (no range)
+   -1			Key is less than range
+    1			Key is larger than range
+*/
+
+int handler::compare_key(key_range *range)
+{
+  KEY_PART_INFO *key_part= range_key_part;
+  uint store_length;
+
+  if (!range)
+    return 0;					// No max range
+
+  for (const char *key=range->key, *end=key+range->length;
+       key < end;
+       key+= store_length, key_part++)
+  {
+    int cmp;
+    store_length= key_part->store_length;
+    if (key_part->null_bit)
+    {
+      if (*key)
+      {
+	if (!key_part->field->is_null())
+	  return 1;
+	continue;
+      }
+      else if (key_part->field->is_null())
+	return 0;
+      key++;					// Skip null byte
+      store_length--;
+    }
+    if ((cmp=key_part->field->key_cmp((byte*) key, key_part->length)) < 0)
+      return -1;
+    if (cmp > 0)
+      return 1;
+  }
+  return key_compare_result_on_equal;
+}

sql/handler.h

@@ -204,6 +204,14 @@ typedef struct st_ha_check_opt
 } HA_CHECK_OPT;
 
 
+typedef struct st_key_range
+{
+  const byte *key;
+  uint length;
+  enum ha_rkey_function flag;
+} key_range;
+
+
 class handler :public Sql_alloc
 {
  protected:
@@ -225,6 +233,12 @@ class handler :public Sql_alloc
   time_t create_time;			/* When table was created */
   time_t check_time;
   time_t update_time;
+
+  /* The following are for read_range() */
+  key_range save_end_range, *end_range;
+  KEY_PART_INFO *range_key_part;
+  int key_compare_result_on_equal;
+
   uint errkey;				/* Last dup key */
   uint sortkey, key_used_on_scan;
   uint active_index;
@@ -236,6 +250,7 @@ class handler :public Sql_alloc
   bool  auto_increment_column_changed;
   bool implicit_emptied;                /* Can be !=0 only if HEAP */
 
+
   handler(TABLE *table_arg) :table(table_arg),
     ref(0), data_file_length(0), max_data_file_length(0), index_file_length(0),
     delete_length(0), auto_increment_value(0),
@@ -285,6 +300,11 @@ class handler :public Sql_alloc
   {
     return (my_errno=HA_ERR_WRONG_COMMAND);
   }
+  virtual int handler::read_range_first(const key_range *start_key,
+					const key_range *end_key,
+					bool sorted);
+  virtual int handler::read_range_next(bool eq_range);
+  int handler::compare_key(key_range *range);
   virtual int ft_init()
     { return -1; }
   virtual FT_INFO *ft_init_ext(uint flags,uint inx,const byte *key, uint keylen)

sql/opt_range.cc

@@ -646,6 +646,7 @@ int SQL_SELECT::test_quick_select(THD *thd, key_map keys_to_use,
     MEM_ROOT *old_root,alloc;
     SEL_TREE *tree;
     KEY_PART *key_parts;
+    KEY *key_info;
     PARAM param;
 
     /* set up parameter that is passed to all functions */
@@ -671,17 +672,17 @@ int SQL_SELECT::test_quick_select(THD *thd, key_map keys_to_use,
     old_root=my_pthread_getspecific_ptr(MEM_ROOT*,THR_MALLOC);
     my_pthread_setspecific_ptr(THR_MALLOC,&alloc);
 
-    for (idx=0 ; idx < head->keys ; idx++)
+    key_info= head->key_info;
+    for (idx=0 ; idx < head->keys ; idx++, key_info++)
     {
+      KEY_PART_INFO *key_part_info;
       if (!keys_to_use.is_set(idx))
 	continue;
-      KEY *key_info= &head->key_info[idx];
-      KEY_PART_INFO *key_part_info= key_info->key_part;
-
       if (key_info->flags & HA_FULLTEXT)
 	continue;    // ToDo: ft-keys in non-ft ranges, if possible   SerG
 
       param.key[param.keys]=key_parts;
+      key_part_info= key_info->key_part;
       for (uint part=0 ; part < key_info->key_parts ;
 	   part++, key_parts++, key_part_info++)
       {
@@ -1167,39 +1168,39 @@ get_mm_leaf(PARAM *param, COND *conf_func, Field *field, KEY_PART *key_part,
     tree->max_flag=NO_MAX_RANGE;
     break;
   case Item_func::SP_EQUALS_FUNC:
-      tree->min_flag=GEOM_FLAG | HA_READ_MBR_EQUAL;// NEAR_MIN;//512;
-      tree->max_flag=NO_MAX_RANGE;
-      break;
+    tree->min_flag=GEOM_FLAG | HA_READ_MBR_EQUAL;// NEAR_MIN;//512;
+    tree->max_flag=NO_MAX_RANGE;
+    break;
   case Item_func::SP_DISJOINT_FUNC:
-      tree->min_flag=GEOM_FLAG | HA_READ_MBR_DISJOINT;// NEAR_MIN;//512;
-      tree->max_flag=NO_MAX_RANGE;
-      break;
+    tree->min_flag=GEOM_FLAG | HA_READ_MBR_DISJOINT;// NEAR_MIN;//512;
+    tree->max_flag=NO_MAX_RANGE;
+    break;
   case Item_func::SP_INTERSECTS_FUNC:
-      tree->min_flag=GEOM_FLAG | HA_READ_MBR_INTERSECT;// NEAR_MIN;//512;
-      tree->max_flag=NO_MAX_RANGE;
-      break;
+    tree->min_flag=GEOM_FLAG | HA_READ_MBR_INTERSECT;// NEAR_MIN;//512;
+    tree->max_flag=NO_MAX_RANGE;
+    break;
   case Item_func::SP_TOUCHES_FUNC:
-      tree->min_flag=GEOM_FLAG | HA_READ_MBR_INTERSECT;// NEAR_MIN;//512;
-      tree->max_flag=NO_MAX_RANGE;
-      break;
+    tree->min_flag=GEOM_FLAG | HA_READ_MBR_INTERSECT;// NEAR_MIN;//512;
+    tree->max_flag=NO_MAX_RANGE;
+    break;
 
   case Item_func::SP_CROSSES_FUNC:
-      tree->min_flag=GEOM_FLAG | HA_READ_MBR_INTERSECT;// NEAR_MIN;//512;
-      tree->max_flag=NO_MAX_RANGE;
-      break;
+    tree->min_flag=GEOM_FLAG | HA_READ_MBR_INTERSECT;// NEAR_MIN;//512;
+    tree->max_flag=NO_MAX_RANGE;
+    break;
   case Item_func::SP_WITHIN_FUNC:
-      tree->min_flag=GEOM_FLAG | HA_READ_MBR_WITHIN;// NEAR_MIN;//512;
-      tree->max_flag=NO_MAX_RANGE;
-      break;
+    tree->min_flag=GEOM_FLAG | HA_READ_MBR_WITHIN;// NEAR_MIN;//512;
+    tree->max_flag=NO_MAX_RANGE;
+    break;
 
   case Item_func::SP_CONTAINS_FUNC:
-      tree->min_flag=GEOM_FLAG | HA_READ_MBR_CONTAIN;// NEAR_MIN;//512;
-      tree->max_flag=NO_MAX_RANGE;
-      break;
+    tree->min_flag=GEOM_FLAG | HA_READ_MBR_CONTAIN;// NEAR_MIN;//512;
+    tree->max_flag=NO_MAX_RANGE;
+    break;
   case Item_func::SP_OVERLAPS_FUNC:
-      tree->min_flag=GEOM_FLAG | HA_READ_MBR_INTERSECT;// NEAR_MIN;//512;
-      tree->max_flag=NO_MAX_RANGE;
-      break;
+    tree->min_flag=GEOM_FLAG | HA_READ_MBR_INTERSECT;// NEAR_MIN;//512;
+    tree->max_flag=NO_MAX_RANGE;
+    break;
 
   default:
     break;
@@ -2343,8 +2344,14 @@ get_quick_select(PARAM *param,uint idx,SEL_ARG *key_tree)
 {
   QUICK_SELECT *quick;
   DBUG_ENTER("get_quick_select");
-  if ((quick=new QUICK_SELECT(param->thd, param->table,
-			      param->real_keynr[idx])))
+
+  if (param->table->key_info[param->real_keynr[idx]].flags & HA_SPATIAL)
+    quick=new QUICK_SELECT_GEOM(param->thd, param->table, param->real_keynr[idx],
+				0);
+  else
+    quick=new QUICK_SELECT(param->thd, param->table, param->real_keynr[idx]);
+			      
+  if (quick)
   {
     if (quick->error ||
 	get_quick_keys(param,quick,param->key[idx],key_tree,param->min_key,0,
@@ -2510,8 +2517,9 @@ static bool null_part_in_key(KEY_PART *key_part, const char *key, uint length)
   return 0;
 }
 
+
 /****************************************************************************
-** Create a QUICK RANGE based on a key
+  Create a QUICK RANGE based on a key
 ****************************************************************************/
 
 QUICK_SELECT *get_quick_select_for_ref(THD *thd, TABLE *table, TABLE_REF *ref)
@@ -2592,115 +2600,74 @@ int QUICK_SELECT::get_next()
   for (;;)
   {
     int result;
+    key_range start_key, end_key;
     if (range)
-    {						// Already read through key
-       result=((range->flag & (EQ_RANGE | GEOM_FLAG)) ?
-	       file->index_next_same(record, (byte*) range->min_key,
-				     range->min_length) :
-	       file->index_next(record));
-
-      if (!result)
-      {
-	if ((range->flag & GEOM_FLAG) || !cmp_next(*it.ref()))
-	  DBUG_RETURN(0);
-      }
-      else if (result != HA_ERR_END_OF_FILE)
+    {
+      // Already read through key
+      result= file->read_range_next(test(range->flag & EQ_RANGE));
+      if (result != HA_ERR_END_OF_FILE)
 	DBUG_RETURN(result);
     }
 
-    if (!(range=it++))
+    if (!(range= it++))
       DBUG_RETURN(HA_ERR_END_OF_FILE);		// All ranges used
 
-    if (range->flag & GEOM_FLAG)
-    {
-      if ((result = file->index_read(record,
-				     (byte*) (range->min_key),
-				     range->min_length,
-				     (ha_rkey_function)(range->flag ^
-							GEOM_FLAG))))
-      {
-        if (result != HA_ERR_KEY_NOT_FOUND)
-	  DBUG_RETURN(result);
-        range=0;				// Not found, to next range
-        continue;
-      }
-      DBUG_RETURN(0);
-    }
+    start_key.key=    range->min_key;
+    start_key.length= range->min_length;
+    start_key.flag=   ((range->flag & NEAR_MIN) ? HA_READ_AFTER_KEY :
+		       (range->flag & EQ_RANGE) ?
+		       HA_READ_KEY_EXACT : HA_READ_KEY_OR_NEXT);
+    end_key.key=      range->max_key;
+    end_key.length=   range->max_length;
+    /*
+      We use READ_AFTER_KEY here because if we are reading on a key
+      prefix we want to find all keys with this prefix
+    */
+    end_key.flag=     (range->flag & NEAR_MAX ? HA_READ_BEFORE_KEY :
+		       HA_READ_AFTER_KEY);
 
-    if (range->flag & NO_MIN_RANGE)		// Read first record
-    {
-      int local_error;
-      if ((local_error=file->index_first(record)))
-	DBUG_RETURN(local_error);		// Empty table
-      if (cmp_next(range) == 0)
-	DBUG_RETURN(0);
-      range=0;			// No matching records; go to next range
-      continue;
-    }
-    if ((result = file->index_read(record,
-				   (byte*) (range->min_key +
-					    test(range->flag & GEOM_FLAG)),
-				   range->min_length,
-				   (range->flag & NEAR_MIN) ?
-				   HA_READ_AFTER_KEY:
-				   (range->flag & EQ_RANGE) ?
-				   HA_READ_KEY_EXACT :
-				   HA_READ_KEY_OR_NEXT)))
+    result= file->read_range_first(range->min_length ? &start_key : 0,
+				   range->max_length ? &end_key : 0,
+				   sorted);
+    if (range->flag == (UNIQUE_RANGE | EQ_RANGE))
+      range=0;				// Stop searching
 
-    {
-      if (result != HA_ERR_KEY_NOT_FOUND)
-	DBUG_RETURN(result);
-      range=0;					// Not found, to next range
-      continue;
-    }
-    if (cmp_next(range) == 0)
-    {
-      if (range->flag == (UNIQUE_RANGE | EQ_RANGE))
-	range=0;				// Stop searching
-      DBUG_RETURN(0);				// Found key is in range
-    }
-    range=0;					// To next range
+    if (result != HA_ERR_END_OF_FILE)
+      DBUG_RETURN(result);
+    range=0;				// No matching rows; go to next range
   }
 }
 
 
-/*
-  Compare if found key is over max-value
-  Returns 0 if key <= range->max_key
-*/
+/* Get next for geometrical indexes */
 
-int QUICK_SELECT::cmp_next(QUICK_RANGE *range_arg)
+int QUICK_SELECT_GEOM::get_next()
 {
-  if (range_arg->flag & NO_MAX_RANGE)
-    return 0;					/* key can't be to large */
+  DBUG_ENTER(" QUICK_SELECT_GEOM::get_next");
 
-  KEY_PART *key_part=key_parts;
-  uint store_length;
-  for (char *key=range_arg->max_key, *end=key+range_arg->max_length;
-       key < end;
-       key+= store_length, key_part++)
+  for (;;)
   {
-    int cmp;
-    store_length= key_part->store_length;
-    if (key_part->null_bit)
+    int result;
+    if (range)
     {
-      if (*key)
-      {
-	if (!key_part->field->is_null())
-	  return 1;
-	continue;
-      }
-      else if (key_part->field->is_null())
-	return 0;
-      key++;					// Skip null byte
-      store_length--;
+      // Already read through key
+      result= file->index_next_same(record, (byte*) range->min_key,
+				    range->min_length);
+      if (result != HA_ERR_END_OF_FILE)
+	DBUG_RETURN(result);
     }
-    if ((cmp=key_part->field->key_cmp((byte*) key, key_part->length)) < 0)
-      return 0;
-    if (cmp > 0)
-      return 1;
+
+    if (!(range= it++))
+      DBUG_RETURN(HA_ERR_END_OF_FILE);		// All ranges used
+
+    result= file->index_read(record,
+			     (byte*) range->min_key,
+			     range->min_length,
+			     (ha_rkey_function)(range->flag ^ GEOM_FLAG));
+    if (result != HA_ERR_KEY_NOT_FOUND)
+      DBUG_RETURN(result);
+    range=0;				// Not found, to next range
   }
-  return (range_arg->flag & NEAR_MAX) ? 1 : 0;	// Exact match
 }
 
 
@@ -2966,7 +2933,7 @@ print_key(KEY_PART *key_part,const char *key,uint used_length)
   for (; key < key_end; key+=store_length, key_part++)
   {
     Field *field=      key_part->field;
-    uint store_length= key_part->store_length;
+    store_length= key_part->store_length;
 
     if (field->real_maybe_null())
     {
@@ -2975,7 +2942,7 @@ print_key(KEY_PART *key_part,const char *key,uint used_length)
 	fwrite("NULL",sizeof(char),4,DBUG_FILE);
 	continue;
       }
-      key++;
+      key++;					// Skip null byte
       store_length--;
     }
     field->set_key_image((char*) key, key_part->length, field->charset());

sql/opt_range.h

@@ -89,11 +89,20 @@ class QUICK_SELECT {
   int init() { return error=file->index_init(index); }
   virtual int get_next();
   virtual bool reverse_sorted() { return 0; }
-  int cmp_next(QUICK_RANGE *range);
   bool unique_key_range();
 };
 
 
+class QUICK_SELECT_GEOM: public QUICK_SELECT
+{
+public:
+  QUICK_SELECT_GEOM(THD *thd, TABLE *table, uint index_arg, bool no_alloc)
+    :QUICK_SELECT(thd, table, index_arg, no_alloc)
+    {};
+  virtual int get_next();
+};
+
+
 class QUICK_SELECT_DESC: public QUICK_SELECT
 {
 public:

sql/sql_select.cc

@@ -3744,7 +3744,8 @@ make_join_readinfo(JOIN *join, uint options)
 	    table->key_read=1;
 	    table->file->extra(HA_EXTRA_KEYREAD);
 	  }
-	  else if (!table->used_keys.is_clear_all() && ! (tab->select && tab->select->quick))
+	  else if (!table->used_keys.is_clear_all() &&
+		   !(tab->select && tab->select->quick))
 	  {					// Only read index tree
 	    tab->index=find_shortest_key(table, & table->used_keys);
 	    tab->table->file->index_init(tab->index);
@@ -6905,6 +6906,7 @@ static int test_if_order_by_key(ORDER *order, TABLE *table, uint idx,
   key_part_end=key_part+table->key_info[idx].key_parts;
   key_part_map const_key_parts=table->const_key_parts[idx];
   int reverse=0;
+  DBUG_ENTER("test_if_order_by_key");
 
   for (; order ; order=order->next, const_key_parts>>=1)
   {
@@ -6915,25 +6917,24 @@ static int test_if_order_by_key(ORDER *order, TABLE *table, uint idx,
       Skip key parts that are constants in the WHERE clause.
       These are already skipped in the ORDER BY by const_expression_in_where()
     */
-    while (const_key_parts & 1)
-    {
-      key_part++; const_key_parts>>=1;
-    }
+    for (; const_key_parts & 1 ; const_key_parts>>= 1)
+      key_part++; 
+
     if (key_part == key_part_end || key_part->field != field)
-      return 0;
+      DBUG_RETURN(0);
 
     /* set flag to 1 if we can use read-next on key, else to -1 */
-    flag=(order->asc == !(key_part->key_part_flag & HA_REVERSE_SORT))
-      ? 1 : -1;
+    flag= ((order->asc == !(key_part->key_part_flag & HA_REVERSE_SORT)) ? 1 : -1);
     if (reverse && flag != reverse)
-      return 0;
+      DBUG_RETURN(0);
     reverse=flag;				// Remember if reverse
     key_part++;
   }
   *used_key_parts= (uint) (key_part - table->key_info[idx].key_part);
-  return reverse;
+  DBUG_RETURN(reverse);
 }
 
+
 static uint find_shortest_key(TABLE *table, const key_map *usable_keys)
 {
   uint min_length= (uint) ~0;
@@ -6956,18 +6957,20 @@ static uint find_shortest_key(TABLE *table, const key_map *usable_keys)
 }
 
 /*
+  Test if a second key is the subkey of the first one.
+
   SYNOPSIS
     is_subkey()
-    key_part		- first key parts
-    ref_key_part	- second key parts
-    ref_key_part_end	- last+1 part of the second key
-  DESCRIPTION
-    Test if a second key is the subkey of the first one.
+    key_part		First key parts
+    ref_key_part	Second key parts
+    ref_key_part_end	Last+1 part of the second key
+
   NOTE
     Second key MUST be shorter than the first one.
+
   RETURN
-    1	- is the subkey
-    0	- otherwise
+    1	is a subkey
+    0	no sub key
 */
 
 inline bool 
@@ -6981,20 +6984,21 @@ is_subkey(KEY_PART_INFO *key_part, KEY_PART_INFO *ref_key_part,
 }
 
 /*
+  Test if we can use one of the 'usable_keys' instead of 'ref' key for sorting
+
   SYNOPSIS
     test_if_subkey()
-    ref		- number of key, used for WHERE clause
-    usable_keys - keys for testing
-  DESCRIPTION
-    Test if we can use one of the 'usable_keys' instead of 'ref' key.
+    ref			Number of key, used for WHERE clause
+    usable_keys		Keys for testing
+
   RETURN
-    MAX_KEY			- if we can't use other key
-    the number of found key	- otherwise
+    MAX_KEY			If we can't use other key
+    the number of found key	Otherwise
 */
 
 static uint
 test_if_subkey(ORDER *order, TABLE *table, uint ref, uint ref_key_parts,
-	       const key_map& usable_keys)
+	       const key_map *usable_keys)
 {
   uint nr;
   uint min_length= (uint) ~0;
@@ -7005,7 +7009,7 @@ test_if_subkey(ORDER *order, TABLE *table, uint ref, uint ref_key_parts,
 
   for (nr= 0 ; nr < table->keys ; nr++)
   {
-    if (usable_keys.is_set(nr) &&
+    if (usable_keys->is_set(nr) &&
 	table->key_info[nr].key_length < min_length &&
 	table->key_info[nr].key_parts >= ref_key_parts &&
 	is_subkey(table->key_info[nr].key_part, ref_key_part,
@@ -7049,12 +7053,12 @@ test_if_skip_sort_order(JOIN_TAB *tab,ORDER *order,ha_rows select_limit,
     if ((*tmp_order->item)->type() != Item::FIELD_ITEM)
     {
       usable_keys.clear_all();
-      break;
+      DBUG_RETURN(0);
     }
-    usable_keys.intersect(
-        ((Item_field*) (*tmp_order->item))->field->part_of_sortkey);
+    usable_keys.intersect(((Item_field*) (*tmp_order->item))->
+			  field->part_of_sortkey);
     if (usable_keys.is_clear_all())
-      break;					// No usable keys
+      DBUG_RETURN(0);					// No usable keys
   }
 
   ref_key= -1;
@@ -7090,9 +7094,9 @@ test_if_skip_sort_order(JOIN_TAB *tab,ORDER *order,ha_rows select_limit,
 	keys
       */
       if (table->used_keys.is_set(ref_key))
-	usable_keys.merge(table->used_keys);
+	usable_keys.intersect(table->used_keys);
       if ((new_ref_key= test_if_subkey(order, table, ref_key, ref_key_parts,
-				       usable_keys)) < MAX_KEY)
+				       &usable_keys)) < MAX_KEY)
       {
 	/* Found key that can be used to retrieve data in sorted order */
 	if (tab->ref.key >= 0)
@@ -7292,9 +7296,9 @@ create_sort_index(THD *thd, JOIN *join, ORDER *order,
 	For impossible ranges (like when doing a lookup on NULL on a NOT NULL
 	field, quick will contain an empty record set.
       */
-      if (!(select->quick= tab->type == JT_FT ?
-			   new FT_SELECT(thd, table, tab->ref.key) :
-			   get_quick_select_for_ref(thd, table, &tab->ref)))
+      if (!(select->quick= (tab->type == JT_FT ?
+			    new FT_SELECT(thd, table, tab->ref.key) :
+			    get_quick_select_for_ref(thd, table, &tab->ref))))
 	goto err;
     }
   }