diff options
Diffstat (limited to 'sql/sql_sort.h')
| -rw-r--r-- | sql/sql_sort.h | 139 |
1 files changed, 110 insertions, 29 deletions
diff --git a/sql/sql_sort.h b/sql/sql_sort.h index 4f53bc53a3f..50fea16b4f7 100644 --- a/sql/sql_sort.h +++ b/sql/sql_sort.h @@ -20,8 +20,6 @@ #include <my_sys.h> /* qsort2_cmp */ #include "queues.h" -typedef struct st_buffpek BUFFPEK; - struct SORT_FIELD; class Field; struct TABLE; @@ -63,6 +61,88 @@ struct BUFFPEK_COMPARE_CONTEXT void *key_compare_arg; }; +struct Merge_chunk { +public: + Merge_chunk(): m_current_key(NULL), + m_file_position(0), + m_buffer_start(NULL), + m_buffer_end(NULL), + m_rowcount(0), + m_mem_count(0), + m_max_keys(0) + {} + + my_off_t file_position() const { return m_file_position; } + void set_file_position(my_off_t val) { m_file_position= val; } + void advance_file_position(my_off_t val) { m_file_position+= val; } + + uchar *buffer_start() { return m_buffer_start; } + const uchar *buffer_end() const { return m_buffer_end; } + + void set_buffer(uchar *start, uchar *end) + { + m_buffer_start= start; + m_buffer_end= end; + } + void set_buffer_start(uchar *start) + { + m_buffer_start= start; + } + void set_buffer_end(uchar *end) + { + DBUG_ASSERT(m_buffer_end == NULL || end <= m_buffer_end); + m_buffer_end= end; + } + + void init_current_key() { m_current_key= m_buffer_start; } + uchar *current_key() { return m_current_key; } + void advance_current_key(uint val) { m_current_key+= val; } + + void decrement_rowcount(ha_rows val) { m_rowcount-= val; } + void set_rowcount(ha_rows val) { m_rowcount= val; } + ha_rows rowcount() const { return m_rowcount; } + + ha_rows mem_count() const { return m_mem_count; } + void set_mem_count(ha_rows val) { m_mem_count= val; } + ha_rows decrement_mem_count() { return --m_mem_count; } + + ha_rows max_keys() const { return m_max_keys; } + void set_max_keys(ha_rows val) { m_max_keys= val; } + + size_t buffer_size() const { return m_buffer_end - m_buffer_start; } + + /** + Tries to merge *this with *mc, returns true if successful. + The assumption is that *this is no longer in use, + and the space it has been allocated can be handed over to a + buffer which is adjacent to it. + */ + bool merge_freed_buff(Merge_chunk *mc) const + { + if (mc->m_buffer_end == m_buffer_start) + { + mc->m_buffer_end= m_buffer_end; + mc->m_max_keys+= m_max_keys; + return true; + } + else if (mc->m_buffer_start == m_buffer_end) + { + mc->m_buffer_start= m_buffer_start; + mc->m_max_keys+= m_max_keys; + return true; + } + return false; + } + + uchar *m_current_key; /// The current key for this chunk. + my_off_t m_file_position;/// Current position in the file to be sorted. + uchar *m_buffer_start; /// Start of main-memory buffer for this chunk. + uchar *m_buffer_end; /// End of main-memory buffer for this chunk. + ha_rows m_rowcount; /// Number of unread rows in this chunk. + ha_rows m_mem_count; /// Number of rows in the main-memory buffer. + ha_rows m_max_keys; /// If we have fixed-size rows: + /// max number of rows in buffer. +}; typedef Bounds_checked_array<SORT_ADDON_FIELD> Addon_fields_array; @@ -78,8 +158,8 @@ class Addon_fields { public: Addon_fields(Addon_fields_array arr) : m_field_descriptors(arr), - m_addon_buf(NULL), - m_addon_buf_length(0), + m_addon_buf(), + m_addon_buf_length(), m_using_packed_addons(false) { DBUG_ASSERT(!arr.is_null()); @@ -87,25 +167,24 @@ public: SORT_ADDON_FIELD *begin() { return m_field_descriptors.begin(); } SORT_ADDON_FIELD *end() { return m_field_descriptors.end(); } - size_t num_field_descriptors() const { return m_field_descriptors.size(); } -/* - /// rr_unpack_from_tempfile needs an extra buffer when unpacking. + /// rr_unpack_from_tempfile needs an extra buffer when unpacking. uchar *allocate_addon_buf(uint sz) { - if (m_addon_buf != NULL) - { - DBUG_ASSERT(m_addon_buf_length == sz); - return m_addon_buf; - } - m_addon_buf= static_cast<uchar*>(sql_alloc(sz)); + m_addon_buf= (uchar *)my_malloc(sz, MYF(MY_WME | MY_THREAD_SPECIFIC)); if (m_addon_buf) m_addon_buf_length= sz; return m_addon_buf; } -*/ - uchar *get_addon_buf() { return m_addon_buf; } + void free_addon_buff() + { + my_free(m_addon_buf); + m_addon_buf= NULL; + m_addon_buf_length= 0; + } + + uchar *get_addon_buf() { return m_addon_buf; } uint get_addon_buf_length() const { return m_addon_buf_length; } void set_using_packed_addons(bool val) @@ -165,10 +244,12 @@ public: ha_rows max_rows; // Select limit, or HA_POS_ERROR if unlimited. ha_rows examined_rows; // Number of examined rows. TABLE *sort_form; // For quicker make_sortkey. - SORT_FIELD *local_sortorder; - SORT_FIELD *end; + /** + ORDER BY list with some precalculated info for filesort. + Array is created and owned by a Filesort instance. + */ + Bounds_checked_array<SORT_FIELD> local_sortorder; Addon_fields *addon_fields; // Descriptors for companion fields. - LEX_STRING addon_buf; // Buffer & length of added packed fields. bool using_pq; uchar *unique_buff; @@ -227,19 +308,19 @@ private: bool m_using_packed_addons; ///< caches the value of using_packed_addons() }; +typedef Bounds_checked_array<uchar> Sort_buffer; -int merge_many_buff(Sort_param *param, uchar *sort_buffer, size_t buff_size, - BUFFPEK *buffpek, - uint *maxbuffer, IO_CACHE *t_file); -ulong read_to_buffer(IO_CACHE *fromfile,BUFFPEK *buffpek, +int merge_many_buff(Sort_param *param, Sort_buffer sort_buffer, + Merge_chunk *buffpek, uint *maxbuffer, IO_CACHE *t_file); +ulong read_to_buffer(IO_CACHE *fromfile, Merge_chunk *buffpek, Sort_param *param); bool merge_buffers(Sort_param *param,IO_CACHE *from_file, - IO_CACHE *to_file, uchar *sort_buffer, size_t buff_size, - BUFFPEK *lastbuff,BUFFPEK *Fb, - BUFFPEK *Tb,int flag); -int merge_index(Sort_param *param, uchar *sort_buffer, size_t buff_size, - BUFFPEK *buffpek, uint maxbuffer, - IO_CACHE *tempfile, IO_CACHE *outfile); -void reuse_freed_buff(QUEUE *queue, BUFFPEK *reuse, uint key_length); + IO_CACHE *to_file, Sort_buffer sort_buffer, + Merge_chunk *lastbuff, Merge_chunk *Fb, + Merge_chunk *Tb, int flag); +int merge_index(Sort_param *param, Sort_buffer sort_buffer, + Merge_chunk *buffpek, uint maxbuffer, + IO_CACHE *tempfile, IO_CACHE *outfile); +void reuse_freed_buff(QUEUE *queue, Merge_chunk *reuse, uint key_length); #endif /* SQL_SORT_INCLUDED */ |