Commit 3712931c authored by monty@hundin.mysql.fi's avatar monty@hundin.mysql.fi
Browse files

Fixed bug in ORDER BY ... LIMIT

parent b8a8c5e3

Docs/manual.texi

+3 −0
Original line number Diff line number Diff line
@@ -50797,6 +50797,9 @@ each individual 4.0.x release. 
@appendixsubsec Changes in release 4.0.5

@itemize

@item

Fixed a newly introduced bug that caused @code{ORDER BY ... LIMIT #}

to not return all rows.

@item

Fixed a bug in multi-table deletes when outer join is used on an empty

table, which get's first to be deleted

@item

sql/sql_select.cc

+32 −9
Original line number Diff line number Diff line
@@ -111,7 +111,8 @@ static Item* part_of_refkey(TABLE *form,Field *field); 
static uint find_shortest_key(TABLE *table, key_map usable_keys);

static bool test_if_skip_sort_order(JOIN_TAB *tab,ORDER *order,

				    ha_rows select_limit, bool no_changes);

static int create_sort_index(JOIN_TAB *tab,ORDER *order,ha_rows select_limit);

static int create_sort_index(JOIN_TAB *tab,ORDER *order,ha_rows filesort_limit,

			     ha_rows select_limit);

static int remove_duplicates(JOIN *join,TABLE *entry,List<Item> &fields,

			     Item *having);

static int remove_dup_with_compare(THD *thd, TABLE *entry, Field **field,
@@ -207,6 +208,7 @@ mysql_select(THD *thd,TABLE_LIST *tables,List<Item> &fields,COND *conds, 
  int		error, tmp_error;

  bool		need_tmp,hidden_group_fields;

  bool		simple_order,simple_group,no_order, skip_sort_order;

  ha_rows	select_limit;

  Item::cond_result cond_value;

  SQL_SELECT	*select;

  DYNAMIC_ARRAY keyuse;
@@ -662,7 +664,7 @@ mysql_select(THD *thd,TABLE_LIST *tables,List<Item> &fields,COND *conds, 
      DBUG_PRINT("info",("Sorting for group"));

      thd->proc_info="Sorting for group";

      if (create_sort_index(&join.join_tab[join.const_tables],group,

			    HA_POS_ERROR) ||

			    HA_POS_ERROR, HA_POS_ERROR) ||

	  make_sum_func_list(&join,all_fields) ||

	  alloc_group_fields(&join,group))

	goto err;
@@ -677,7 +679,7 @@ mysql_select(THD *thd,TABLE_LIST *tables,List<Item> &fields,COND *conds, 
	DBUG_PRINT("info",("Sorting for order"));

	thd->proc_info="Sorting for order";

	if (create_sort_index(&join.join_tab[join.const_tables],order,

			      HA_POS_ERROR))

			      HA_POS_ERROR, HA_POS_ERROR))

	  goto err;				/* purecov: inspected */

	order=0;

      }
@@ -778,7 +780,7 @@ mysql_select(THD *thd,TABLE_LIST *tables,List<Item> &fields,COND *conds, 
      if (group)

      {

	thd->proc_info="Creating sort index";

	if (create_sort_index(join.join_tab,group,HA_POS_ERROR) ||

	if (create_sort_index(join.join_tab,group,HA_POS_ERROR, HA_POS_ERROR) ||

	    alloc_group_fields(&join,group))

	{

	  free_tmp_table(thd,tmp_table2);	/* purecov: inspected */
@@ -872,11 +874,31 @@ mysql_select(THD *thd,TABLE_LIST *tables,List<Item> &fields,COND *conds, 
	DBUG_EXECUTE("where",print_where(conds,"having after sort"););

      }

    }

    select_limit= thd->select_limit;

    if (having || group || (join.select_options & OPTION_FOUND_ROWS))

      select_limit= HA_POS_ERROR;

    else

    {

      /*

	We can abort sorting after thd->select_limit rows if we there is no

	WHERE clause for any tables after the sorted one.

      */

      JOIN_TAB *table= &join.join_tab[join.const_tables+1];

      JOIN_TAB *end_table= &join.join_tab[join.tables];

      for (; table < end_table ; table++)

      {

	if (table->select_cond)

	{

	  /* We have to sort all rows */

	  select_limit= HA_POS_ERROR;

	  break;

	}

      }

    }

    if (create_sort_index(&join.join_tab[join.const_tables],

			  group ? group : order,

			  (having || group ||

			   (join.select_options & OPTION_FOUND_ROWS)) ?

			  HA_POS_ERROR : thd->select_limit))

			  select_limit, 

			  thd->select_limit))

      goto err; /* purecov: inspected */

  }

  join.having=having;				// Actually a parameter
@@ -5639,7 +5661,8 @@ test_if_skip_sort_order(JOIN_TAB *tab,ORDER *order,ha_rows select_limit, 
*****************************************************************************/



static int

create_sort_index(JOIN_TAB *tab,ORDER *order,ha_rows select_limit)

create_sort_index(JOIN_TAB *tab, ORDER *order, ha_rows filesort_limit,

		  ha_rows select_limit)

{

  SORT_FIELD *sortorder;

  uint length;
@@ -5684,7 +5707,7 @@ create_sort_index(JOIN_TAB *tab,ORDER *order,ha_rows select_limit) 
  if (table->tmp_table)

    table->file->info(HA_STATUS_VARIABLE);	// Get record count

  table->found_records=filesort(table,sortorder,length,

				select, 0L, select_limit, &examined_rows);

				select, 0L, filesort_limit, &examined_rows);

  tab->records=table->found_records;		// For SQL_CALC_ROWS

  delete select;				// filesort did select

  tab->select=0;