[Maria-developers] review: [Commits] Rev 2946: Fix LP BUG#715738 in file:///home/tsk/mprog/src/5.3/
Hi!
"timour" == timour <timour@askmonty.org> writes:
timour> At file:///home/tsk/mprog/src/5.3/ timour> ------------------------------------------------------------ timour> revno: 2946 timour> revision-id: timour@askmonty.org-20110322132154-moeuyey4saatnm5x timour> parent: igor@askmonty.org-20110315193048-akp4yq0y079dkkx2 timour> committer: timour@askmonty.org timour> branch nick: 5.3 timour> timestamp: Tue 2011-03-22 15:21:54 +0200 timour> message: timour> Fix LP BUG#715738 timour> Analysis: timour> A query with implicit grouping is one with aggregate functions and timour> no GROUP BY clause. MariaDB inherits from MySQL an SQL extenstion timour> that allows mixing aggregate functions with non-aggregate fields. timour> If a query with such mixed select clause produces an empty result timour> set, the meaning of aggregate functions is well defined - either timour> NULL (MIN, MAX, etc.), or 0 (count(*)). However the non-aggregated timour> fields must also have some value, and the only reasonable value in timour> the case of empty result is NULL. <cut> === modified file 'sql/sql_lex.cc' --- a/sql/sql_lex.cc 2011-03-09 13:47:59 +0000 +++ b/sql/sql_lex.cc 2011-03-22 13:21:54 +0000 @@ -1667,6 +1667,11 @@ void st_select_lex::init_select() cond_value= having_value= Item::COND_UNDEF; inner_refs_list.empty(); full_group_by_flag= 0; + n_sum_items= 0; + n_child_sum_items= 0; + select_n_sum_item= 0; + select_n_nonsum_item= 0; + ok, but I am not totally happy with that we get even more things that needs to be initialized for every select (we already initialize a lot of things...) Please change the names of 'n_' to something more understandable. 'number_of_' or 'use the _count' prefix that we use in other places. === modified file 'sql/sql_yacc.yy' --- a/sql/sql_yacc.yy 2011-03-09 13:47:59 +0000 +++ b/sql/sql_yacc.yy 2011-03-22 13:21:54 +0000 @@ -1338,7 +1338,7 @@ bool my_yyoverflow(short **a, YYSTYPE ** ev_alter_on_schedule_completion opt_ev_rename_to opt_ev_sql_stmt %type <ulong_num> - ulong_num real_ulong_num merge_insert_types + ulong_num real_ulong_num merge_insert_types remember_n_sum_func %type <ulonglong_number> ulonglong_num real_ulonglong_num size_number @@ -7019,31 +7019,43 @@ select_item_list: ; select_item: - remember_name select_item2 remember_end select_alias + remember_n_sum_func remember_name select_item2 remember_end select_alias { THD *thd= YYTHD; - DBUG_ASSERT($1 < $3); + DBUG_ASSERT($2 < $4); - if (add_item_to_list(thd, $2)) + if (thd->lex->current_select->n_sum_items > $1) + ++thd->lex->current_select->select_n_sum_item; + else + ++thd->lex->current_select->select_n_nonsum_item; Not sure if the counting of select_n_nonsum_item is correct. For example, we may have an item: SELECT MAX(field)+const_field from t1 ... In this case 'MAX(field)+const_field' will be counted as select_n_sum_item even if it should be counted also as select_n_nonsum_item. Not sure we can do this test properly at the parsing stage... Regards, Monty
participants (1)
-
Michael Widenius