diff options
| -rw-r--r-- | mysql-test/r/count_distinct.result | 25 | ||||
| -rw-r--r-- | mysql-test/t/count_distinct.test | 29 | ||||
| -rw-r--r-- | sql/sql_class.h | 2 | ||||
| -rw-r--r-- | sql/uniques.cc | 12 |
4 files changed, 63 insertions, 5 deletions
diff --git a/mysql-test/r/count_distinct.result b/mysql-test/r/count_distinct.result index d55a232c715..760b2710586 100644 --- a/mysql-test/r/count_distinct.result +++ b/mysql-test/r/count_distinct.result @@ -106,3 +106,28 @@ count(distinct user_id) 17 drop table t1; set @@tmp_table_size = default; +create table t1 ( +a VARCHAR(1020), +b int +); +insert into t1 values +( 0 , 1 ), +( 1 , 2 ), +( 2 , 3 ), +( 3 , 4 ), +( 4 , 5 ), +( 5 , 6 ), +( 6 , 7 ), +( 7 , 8 ), +( 8 , 9 ), +( 9 , 10 ), +( 0 , 11 ), +( 1 , 12 ), +( 2 , 13 ), +( 3 , 14 ); +set @@tmp_table_size=1024; +select count(distinct a) from t1; +count(distinct a) +10 +drop table t1; +set @@tmp_table_size = default; diff --git a/mysql-test/t/count_distinct.test b/mysql-test/t/count_distinct.test index a00574b6cba..86045e862e7 100644 --- a/mysql-test/t/count_distinct.test +++ b/mysql-test/t/count_distinct.test @@ -121,5 +121,34 @@ drop table t1; set @@tmp_table_size = default; # +# MDEV-13457: Wrong result for aggregate function with distinct clause when the value for +# tmp_table_size is small +# + +create table t1 ( +a VARCHAR(1020), +b int +); +insert into t1 values +( 0 , 1 ), +( 1 , 2 ), +( 2 , 3 ), +( 3 , 4 ), +( 4 , 5 ), +( 5 , 6 ), +( 6 , 7 ), +( 7 , 8 ), +( 8 , 9 ), +( 9 , 10 ), +( 0 , 11 ), +( 1 , 12 ), +( 2 , 13 ), +( 3 , 14 ); +set @@tmp_table_size=1024; +select count(distinct a) from t1; +drop table t1; +set @@tmp_table_size = default; + +# # End of 5.5 tests # diff --git a/sql/sql_class.h b/sql/sql_class.h index 5dd7cd18a5d..f4be996c9a9 100644 --- a/sql/sql_class.h +++ b/sql/sql_class.h @@ -3919,7 +3919,7 @@ public: { DBUG_ENTER("unique_add"); DBUG_PRINT("info", ("tree %u - %lu", tree.elements_in_tree, max_elements)); - if (!(tree.flag & TREE_ONLY_DUPS) && + if (!(tree.flag & TREE_ONLY_DUPS) && tree.elements_in_tree >= max_elements && flush()) DBUG_RETURN(1); DBUG_RETURN(!tree_insert(&tree, ptr, 0, tree.custom_arg)); diff --git a/sql/uniques.cc b/sql/uniques.cc index 8b7da7e6e52..89ab4682829 100644 --- a/sql/uniques.cc +++ b/sql/uniques.cc @@ -96,6 +96,9 @@ Unique::Unique(qsort_cmp2 comp_func, void * comp_func_fixed_arg, */ max_elements= (ulong) (max_in_memory_size / ALIGN_SIZE(sizeof(TREE_ELEMENT)+size)); + if (!max_elements) + max_elements= 1; + (void) open_cached_file(&file, mysql_tmpdir,TEMP_PREFIX, DISK_BUFFER_SIZE, MYF(MY_WME)); } @@ -608,10 +611,11 @@ bool Unique::walk(TABLE *table, tree_walk_action action, void *walk_action_arg) if (flush_io_cache(&file) || reinit_io_cache(&file, READ_CACHE, 0L, 0, 0)) return 1; /* - merge_buffer must fit at least MERGEBUFF2 keys, because - merge_index() can merge that many BUFFPEKs at once. + merge_buffer must fit at least MERGEBUFF2 + 1 keys, because + merge_index() can merge that many BUFFPEKs at once. The extra space for one key + is needed when a piece of merge buffer is re-read, see merge_walk() */ - size_t buff_sz= max(MERGEBUFF2, max_in_memory_size/full_size+1) * full_size; + size_t buff_sz= max(MERGEBUFF2+1, max_in_memory_size/full_size+1) * full_size; if (!(merge_buffer = (uchar *)my_malloc(buff_sz, MYF(MY_WME)))) return 1; if (buff_sz < (ulong) (full_size * (file_ptrs.elements + 1))) @@ -673,7 +677,7 @@ bool Unique::merge(TABLE *table, uchar *buff, bool without_last_merge) full_size; sort_param.min_dupl_count= min_dupl_count; sort_param.res_length= 0; - sort_param.keys= (uint) (max_in_memory_size / sort_param.sort_length); + sort_param.keys= (uint) max((max_in_memory_size / sort_param.sort_length), MERGEBUFF2); sort_param.not_killable= 1; sort_param.unique_buff= buff + (sort_param.keys * sort_param.sort_length); |