diff options
Diffstat (limited to 'sql/sql_select.cc')
| -rw-r--r-- | sql/sql_select.cc | 84 |
1 files changed, 46 insertions, 38 deletions
diff --git a/sql/sql_select.cc b/sql/sql_select.cc index b40c98cbb52..08fbf753997 100644 --- a/sql/sql_select.cc +++ b/sql/sql_select.cc @@ -1950,52 +1950,55 @@ find_best(JOIN *join,table_map rest_tables,uint idx,double record_count, ** Find how much space the prevous read not const tables takes in cache */ +static void calc_used_field_length(THD *thd, JOIN_TAB *join_tab) +{ + uint null_fields,blobs,fields,rec_length; + null_fields=blobs=fields=rec_length=0; + + Field **f_ptr,*field; + for (f_ptr=join_tab->table->field ; (field= *f_ptr) ; f_ptr++) + { + if (field->query_id == thd->query_id) + { + uint flags=field->flags; + fields++; + rec_length+=field->pack_length(); + if (flags & BLOB_FLAG) + blobs++; + if (!(flags & NOT_NULL_FLAG)) + null_fields++; + } + } + if (null_fields) + rec_length+=(join_tab->table->null_fields+7)/8; + if (join_tab->table->maybe_null) + rec_length+=sizeof(my_bool); + if (blobs) + { + uint blob_length=(uint) (join_tab->table->file->mean_rec_length- + (join_tab->table->reclength- rec_length)); + rec_length+=(uint) max(4,blob_length); + } + join_tab->used_fields=fields; + join_tab->used_fieldlength=rec_length; + join_tab->used_blobs=blobs; +} + + static uint cache_record_length(JOIN *join,uint idx) { - uint length; + uint length=0; JOIN_TAB **pos,**end; THD *thd=join->thd; - length=0; for (pos=join->best_ref+join->const_tables,end=join->best_ref+idx ; pos != end ; pos++) { JOIN_TAB *join_tab= *pos; - if (!join_tab->used_fieldlength) - { /* Not calced yet */ - uint null_fields,blobs,fields,rec_length; - null_fields=blobs=fields=rec_length=0; - - Field **f_ptr,*field; - for (f_ptr=join_tab->table->field ; (field= *f_ptr) ; f_ptr++) - { - if (field->query_id == thd->query_id) - { - uint flags=field->flags; - fields++; - rec_length+=field->pack_length(); - if (flags & BLOB_FLAG) - blobs++; - if (!(flags & NOT_NULL_FLAG)) - null_fields++; - } - } - if (null_fields) - rec_length+=(join_tab->table->null_fields+7)/8; - if (join_tab->table->maybe_null) - rec_length+=sizeof(my_bool); - if (blobs) - { - uint blob_length=(uint) (join_tab->table->file->mean_rec_length- - (join_tab->table->reclength- rec_length)); - rec_length+=(uint) max(4,blob_length); - } - join_tab->used_fields=fields; - join_tab->used_fieldlength=rec_length; - join_tab->used_blobs=blobs; - } + if (!join_tab->used_fieldlength) /* Not calced yet */ + calc_used_field_length(thd, join_tab); length+=join_tab->used_fieldlength; } return length; @@ -2319,6 +2322,7 @@ make_join_select(JOIN *join,SQL_SELECT *select,COND *cond) used_tables|=current_map; if (tab->type == JT_REF && tab->quick && + tab->ref.key == tab->quick->index && tab->ref.key_length < tab->quick->max_used_key_length) { /* Range uses longer key; Use this instead of ref on key */ @@ -5781,15 +5785,19 @@ join_init_cache(THD *thd,JOIN_TAB *tables,uint table_count) uint length,blobs,size; CACHE_FIELD *copy,**blob_ptr; JOIN_CACHE *cache; + JOIN_TAB *join_tab; DBUG_ENTER("join_init_cache"); cache= &tables[table_count].cache; cache->fields=blobs=0; - for (i=0 ; i < table_count ; i++) + join_tab=tables; + for (i=0 ; i < table_count ; i++,join_tab++) { - cache->fields+=tables[i].used_fields; - blobs+=tables[i].used_blobs; + if (!join_tab->used_fieldlength) /* Not calced yet */ + calc_used_field_length(thd, join_tab); + cache->fields+=join_tab->used_fields; + blobs+=join_tab->used_blobs; } if (!(cache->field=(CACHE_FIELD*) sql_alloc(sizeof(CACHE_FIELD)*(cache->fields+table_count*2)+(blobs+1)* |