diff options
Diffstat (limited to 'sql')
| -rw-r--r-- | sql/filesort.cc | 55 |
1 files changed, 32 insertions, 23 deletions
diff --git a/sql/filesort.cc b/sql/filesort.cc index 1d30c23a15e..439a72c42e4 100644 --- a/sql/filesort.cc +++ b/sql/filesort.cc @@ -51,17 +51,38 @@ static int merge_index(SORTPARAM *param,uchar *sort_buffer, static bool save_index(SORTPARAM *param,uchar **sort_keys, uint count); static uint sortlength(SORT_FIELD *sortorder,uint length); - /* - Creates a set of pointers that can be used to read the rows - in sorted order. This should be done with the functions - in records.cc - - Before calling filesort, one must have done - table->file->info(HA_STATUS_VARIABLE) - - The result set is stored in table->io_cache or - table->record_pointers - */ +/* + Sort a table + + SYNOPSIS + filesort() + table Table to sort + sortorder How to sort the table + s_length Number of elements in sortorder + select condition to apply to the rows + special Not used. + (This could be used to sort the rows pointed on by + select->file) + examined_rows Store number of examined rows here + + IMPLEMENTATION + Creates a set of pointers that can be used to read the rows + in sorted order. This should be done with the functions + in records.cc + + REQUIREMENTS + Before calling filesort, one must have done + table->file->info(HA_STATUS_VARIABLE) + + RETURN + HA_POS_ERROR Error + # Number of rows + + examined_rows will be set to number of examined rows + + The result set is stored in table->io_cache or + table->record_pointers +*/ ha_rows filesort(TABLE *table, SORT_FIELD *sortorder, uint s_length, SQL_SELECT *select, ha_rows special, ha_rows max_rows, @@ -127,8 +148,6 @@ ha_rows filesort(TABLE *table, SORT_FIELD *sortorder, uint s_length, records=table->file->estimate_number_of_rows(); selected_records_file= 0; } - if (param.sort_length == param.ref_length && records > param.max_rows) - records=param.max_rows; /* purecov: inspected */ #ifdef USE_STRCOLL if (use_strcoll(default_charset_info) && @@ -372,16 +391,6 @@ static ha_rows find_all_keys(SORTPARAM *param, SQL_SELECT *select, if (write_keys(param,sort_keys,idx,buffpek_pointers,tempfile)) DBUG_RETURN(HA_POS_ERROR); idx=0; - if (param->ref_length == param->sort_length && - my_b_tell(tempfile)/param->sort_length >= param->max_rows) - { - /* - We are writing the result index file and have found all - rows that we need. Abort the sort and return the result. - */ - error=HA_ERR_END_OF_FILE; - break; /* Found enough records */ - } indexpos++; } make_sortkey(param,sort_keys[idx++],ref_pos); |