Commit d61b4b6d authored by Sinisa@sinisa.nasamreza.org's avatar Sinisa@sinisa.nasamreza.org
Browse files

Adding some things according to Monty's correct observations

parent 2f290adb

sql/sql_union.cc

+6 −3
Original line number Diff line number Diff line
@@ -33,7 +33,7 @@ int mysql_union(THD *thd, LEX *lex,select_result *result) 
  TABLE *table;

  int describe=(lex->select_lex.options & SELECT_DESCRIBE) ? 1 : 0;

  int res;

  bool fr=false;

  bool found_rows_for_union=false;

  TABLE_LIST result_table_list;

  TABLE_LIST *first_table=(TABLE_LIST *)lex->select_lex.table_list.first;

  TMP_TABLE_PARAM tmp_table_param;
@@ -61,7 +61,10 @@ int mysql_union(THD *thd, LEX *lex,select_result *result) 
    */

    lex_sl= sl;

    order=  (ORDER *) lex_sl->order_list.first;

    fr = lex->select_lex.options & OPTION_FOUND_ROWS && !describe && sl->select_limit && sl->select_limit != HA_POS_ERROR;

    found_rows_for_union = lex->select_lex.options & OPTION_FOUND_ROWS && !describe && sl->select_limit;

    if (found_rows_for_union)

      lex->select_lex.options ^=  OPTION_FOUND_ROWS;

// This is done to eliminate unnecessary slowing down of the first query 

    if (!order || !describe) 

      last_sl->next=0;				// Remove this extra element

  }
@@ -200,7 +203,7 @@ int mysql_union(THD *thd, LEX *lex,select_result *result) 
		       item_list, NULL, (describe) ? 0 : order,

		       (ORDER*) NULL, NULL, (ORDER*) NULL,

		       thd->options, result);

      if (fr && !res)

      if (found_rows_for_union && !res)

	thd->limit_found_rows = (ulonglong)table->file->records;

    }

  }