diff options
Diffstat (limited to 'sql/item_sum.h')
-rw-r--r-- | sql/item_sum.h | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/sql/item_sum.h b/sql/item_sum.h index 1aa7f78d786..6a62614aff8 100644 --- a/sql/item_sum.h +++ b/sql/item_sum.h @@ -148,19 +148,20 @@ class Item_sum_count_distinct :public Item_sum_int bool fix_fields(THD *thd,TABLE_LIST *tables); TMP_TABLE_PARAM *tmp_table_param; TREE tree; - uint max_elements_in_tree; + // calculated based on max_heap_table_size. If reached, // walk the tree and dump it into MyISAM table + uint max_elements_in_tree; - bool use_tree; // If there are no blobs, we can use a tree, which // is faster than heap table. In that case, we still use the table // to help get things set up, but we insert nothing in it + bool use_tree; - int rec_offset; // the first few bytes of record ( at least one) // are just markers for deleted and NULLs. We want to skip them since // they will just bloat the tree without providing any valuable info + int rec_offset; int tree_to_myisam(); |