/* Copyright (c) 2006, 2013, Oracle and/or its affiliates. All rights reserved. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; version 2 of the License. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */ #ifndef FILESORT_INCLUDED #define FILESORT_INCLUDED class SQL_SELECT; #include "my_global.h" /* uint, uchar */ #include "my_base.h" /* ha_rows */ #include "sql_list.h" /* Sql_alloc */ class SQL_SELECT; class THD; struct TABLE; typedef struct st_sort_field SORT_FIELD; typedef struct st_order ORDER; /** Sorting related info. To be extended by another WL to include complete filesort implementation. */ class Filesort: public Sql_alloc { public: /** List of expressions to order the table by */ ORDER *order; /** Number of records to return */ ha_rows limit; /** ORDER BY list with some precalculated info for filesort */ SORT_FIELD *sortorder; /** select to use for getting records */ SQL_SELECT *select; /** TRUE <=> free select on destruction */ bool own_select; /** true means we are using Priority Queue for order by with limit. */ bool using_pq; Filesort(ORDER *order_arg, ha_rows limit_arg, SQL_SELECT *select_arg): order(order_arg), limit(limit_arg), sortorder(NULL), select(select_arg), own_select(false), using_pq(false) { DBUG_ASSERT(order); }; ~Filesort() { cleanup(); } /* Prepare ORDER BY list for sorting. */ uint make_sortorder(); private: void cleanup(); }; ha_rows filesort(THD *thd, TABLE *table, Filesort *fsort, bool sort_positions, ha_rows *examined_rows, ha_rows *found_rows); void filesort_free_buffers(TABLE *table, bool full); void change_double_for_sort(double nr,uchar *to); class Sort_param; /// Declared here so we can unit test it. void make_sortkey(Sort_param *param, uchar *to, uchar *ref_pos); /// Declared here so we can unit test it. uint sortlength(THD *thd, SORT_FIELD *sortorder, uint s_length, bool *multi_byte_charset); #endif /* FILESORT_INCLUDED */