/* Copyright (c) 2006, 2010, 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 02110-1335 USA */ #ifndef FILESORT_INCLUDED #define FILESORT_INCLUDED #include "my_base.h" /* ha_rows */ #include "sql_alloc.h" #include "filesort_utils.h" class SQL_SELECT; class THD; struct TABLE; class Filesort_tracker; struct SORT_FIELD; struct SORT_FIELD_ATTR; typedef struct st_order ORDER; class JOIN; class Addon_fields; class Sort_keys; /** 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; /* Used with ROWNUM. Contains the number of rows filesort has found so far */ ha_rows *accepted_rows; /** 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; /* TRUE means sort operation must produce table rowids. FALSE means that it also has an option of producing {sort_key, addon_fields} pairs. Usually initialized with value of join_tab->keep_current_rowid to allow for a call to table->file->position() using these table rowids. */ bool sort_positions; /* TRUE means all the fields of table of whose bitmap read_set is set need to be read while reading records in the sort buffer. FALSE otherwise */ bool set_all_read_bits; Filesort_tracker *tracker; Sort_keys *sort_keys; /* Unpack temp table columns to base table columns*/ void (*unpack)(TABLE *); Filesort(ORDER *order_arg, ha_rows limit_arg, bool sort_positions_arg, SQL_SELECT *select_arg): order(order_arg), limit(limit_arg), sortorder(NULL), accepted_rows(0), select(select_arg), own_select(false), using_pq(false), sort_positions(sort_positions_arg), set_all_read_bits(false), sort_keys(NULL), unpack(NULL) { DBUG_ASSERT(order); }; ~Filesort() { cleanup(); } /* Prepare ORDER BY list for sorting. */ Sort_keys* make_sortorder(THD *thd, JOIN *join, table_map first_table_bit); private: void cleanup(); }; class SORT_INFO { /// Buffer for sorting keys. Filesort_buffer filesort_buffer; public: SORT_INFO() :addon_fields(NULL), record_pointers(0), sort_keys(NULL), sorted_result_in_fsbuf(FALSE) { buffpek.str= 0; my_b_clear(&io_cache); } ~SORT_INFO(); void free_data() { close_cached_file(&io_cache); free_addon_buff(); my_free(record_pointers); my_free(buffpek.str); my_free(addon_fields); free_sort_buffer(); } void reset() { free_data(); record_pointers= 0; buffpek.str= 0; addon_fields= 0; sorted_result_in_fsbuf= false; } void free_addon_buff(); IO_CACHE io_cache; /* If sorted through filesort */ LEX_STRING buffpek; /* Buffer for buffpek structures */ Addon_fields *addon_fields; /* Addon field descriptors */ uchar *record_pointers; /* If sorted in memory */ Sort_keys *sort_keys; /* Sort key descriptors*/ /** If the entire result of filesort fits in memory, we skip the merge phase. We may leave the result in filesort_buffer (indicated by sorted_result_in_fsbuf), or we may strip away the sort keys, and copy the sorted result into a new buffer. @see save_index() */ bool sorted_result_in_fsbuf; /* How many rows in final result. Also how many rows in record_pointers, if used */ ha_rows return_rows; ha_rows examined_rows; /* How many rows read */ ha_rows found_rows; /* How many rows was accepted */ /** Sort filesort_buffer */ void sort_buffer(Sort_param *param, uint count) { filesort_buffer.sort_buffer(param, count); } uchar **get_sort_keys() { return filesort_buffer.get_sort_keys(); } uchar *get_sorted_record(uint ix) { return filesort_buffer.get_sorted_record(ix); } uchar *alloc_sort_buffer(uint num_records, uint record_length) { return filesort_buffer.alloc_sort_buffer(num_records, record_length); } void free_sort_buffer() { filesort_buffer.free_sort_buffer(); } bool isfull() const { return filesort_buffer.isfull(); } void init_record_pointers() { filesort_buffer.init_record_pointers(); } void init_next_record_pointer() { filesort_buffer.init_next_record_pointer(); } uchar *get_next_record_pointer() { return filesort_buffer.get_next_record_pointer(); } void adjust_next_record_pointer(uint val) { filesort_buffer.adjust_next_record_pointer(val); } Bounds_checked_array<uchar> get_raw_buf() { return filesort_buffer.get_raw_buf(); } size_t sort_buffer_size() const { return filesort_buffer.sort_buffer_size(); } bool is_allocated() const { return filesort_buffer.is_allocated(); } void set_sort_length(uint val) { filesort_buffer.set_sort_length(val); } uint get_sort_length() const { return filesort_buffer.get_sort_length(); } bool has_filesort_result_in_memory() const { return record_pointers || sorted_result_in_fsbuf; } /// Are we using "addon fields"? bool using_addon_fields() const { return addon_fields != NULL; } /// Are we using "packed addon fields"? bool using_packed_addons(); /** Copies (unpacks) values appended to sorted fields from a buffer back to their regular positions specified by the Field::ptr pointers. @param buff Buffer which to unpack the value from */ template<bool Packed_addon_fields> inline void unpack_addon_fields(uchar *buff); bool using_packed_sortkeys(); friend SORT_INFO *filesort(THD *thd, TABLE *table, Filesort *filesort, Filesort_tracker* tracker, JOIN *join, table_map first_table_bit); }; SORT_INFO *filesort(THD *thd, TABLE *table, Filesort *filesort, Filesort_tracker* tracker, JOIN *join=NULL, table_map first_table_bit=0); bool filesort_use_addons(TABLE *table, uint sortlength, uint *length, uint *fields, uint *null_fields, uint *m_packable_length); void change_double_for_sort(double nr,uchar *to); void store_length(uchar *to, uint length, uint pack_length); void reverse_key(uchar *to, const SORT_FIELD_ATTR *sort_field); #endif /* FILESORT_INCLUDED */