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Commit ec239491 authored by unknown's avatar unknown
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Fix LP BUG#715738 

Analysis:
A query with implicit grouping is one with aggregate functions and
no GROUP BY clause. MariaDB inherits from MySQL an SQL extenstion
that allows mixing aggregate functions with non-aggregate fields.
If a query with such mixed select clause produces an empty result
set, the meaning of aggregate functions is well defined - either
NULL (MIN, MAX, etc.), or 0 (count(*)). However the non-aggregated
fields must also have some value, and the only reasonable value in
the case of empty result is NULL.

The cause of the many wrong results was that if a field is declared
as non-nullable (e.g. because it is a PK or NOT NULL), the semantic
analysis and the optimization phases treat this field as non-nullable,
and generate all related query plan elements based on this assumption.

Later during execution, these incorrectly configured/generated query
plan elements result in a wrong result because the selected fields
are not null due to the not-null assumption during optimization.

Solution:
Detect before the context analysys phase that a query uses implicit
grouping with mixed aggregates/non-aggregates, and set all fields
as nullable. The parser already walks the SELECT clause, and
already sets Item::with_sum_func for Items that reference aggreagate
functions. The patch adds a symmetric Item::with_field so that all
Items that reference an Item_field are marked during their
construction at parse time in the same way as with aggregate function
use.
parent 8aaf9197
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Showing with 670 additions and 5 deletions
mysql-test/r/subselect4.result
View file @ ec239491
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mysql-test/t/subselect4.test
View file @ ec239491
......@@ -685,3 +685,224 @@ WHERE f3 = (
SET SESSION optimizer_switch = @old_optimizer_switch;
drop table t1,t2;
--echo #
--echo # LP BUG#715738: Wrong result with implicit grouping and empty result set
--echo #
CREATE TABLE t1 (f1 int, f2 int);
CREATE TABLE t2 (f3 int, f4 int not null, PRIMARY KEY (f3));
set @save_optimizer_switch=@@optimizer_switch;
SET @@optimizer_switch = 'materialization=on,semijoin=off';
EXPLAIN
SELECT * FROM t1 WHERE (2, 0) NOT IN (SELECT f3, min(f4) FROM t2);
SELECT * FROM t1 WHERE (2, 0) NOT IN (SELECT f3, min(f4) FROM t2);
EXPLAIN
SELECT * FROM t1 WHERE (2, 0) NOT IN (SELECT f3+f4, min(f4) FROM t2);
SELECT * FROM t1 WHERE (2, 0) NOT IN (SELECT f3+f4, min(f4) FROM t2);
EXPLAIN
SELECT * FROM t1 WHERE (2, 0) NOT IN (SELECT f3, min(f4)+max(f4) FROM t2);
SELECT * FROM t1 WHERE (2, 0) NOT IN (SELECT f3, min(f4)+max(f4) FROM t2);
EXPLAIN
SELECT (2, 0) NOT IN (SELECT f3, min(f4) FROM t2) as not_in;
SELECT (2, 0) NOT IN (SELECT f3, min(f4) FROM t2) as not_in;
EXPLAIN
SELECT * FROM t1 WHERE (2, 0) NOT IN (SELECT f3, count(f4) FROM t2);
SELECT * FROM t1 WHERE (2, 0) NOT IN (SELECT f3, count(f4) FROM t2);
EXPLAIN
SELECT * FROM t1 WHERE (2, 0) NOT IN (SELECT f3, f3 + count(f4) FROM t2);
SELECT * FROM t1 WHERE (2, 0) NOT IN (SELECT f3, f3 + count(f4) FROM t2);
EXPLAIN
SELECT (2, 0) NOT IN (SELECT f3, count(f4) FROM t2) as not_in;
SELECT (2, 0) NOT IN (SELECT f3, count(f4) FROM t2) as not_in;
EXPLAIN
SELECT (2, 0) NOT IN (SELECT f3, count(f4) FROM t2 HAVING max(f4) > 7) as not_in;
SELECT (2, 0) NOT IN (SELECT f3, count(f4) FROM t2 HAVING max(f4) > 7) as not_in;
EXPLAIN
SELECT (2, 0) NOT IN (SELECT f3, count(f4) FROM t2 HAVING max(f4) is null) as not_in;
SELECT (2, 0) NOT IN (SELECT f3, count(f4) FROM t2 HAVING max(f4) is null) as not_in;
EXPLAIN
SELECT (2, 0) NOT IN (SELECT max(f3+f3), count(f4) FROM t2) as not_in;
SELECT (2, 0) NOT IN (SELECT max(f3+f3), count(f4) FROM t2) as not_in;
EXPLAIN
SELECT (2, 0) NOT IN (SELECT max(f3+f3), count(f4)+f3 FROM t2) as not_in;
SELECT (2, 0) NOT IN (SELECT max(f3+f3), count(f4)+f3 FROM t2) as not_in;
EXPLAIN
SELECT * FROM t1 WHERE (2, 0) NOT IN (SELECT min(f3)+f3, min(f4)+f3+max(f4) FROM t2);
SELECT * FROM t1 WHERE (2, 0) NOT IN (SELECT min(f3)+f3, min(f4)+f3+max(f4) FROM t2);
SET @@optimizer_switch = 'materialization=off,semijoin=off';
EXPLAIN
SELECT * FROM t1 WHERE (2, 0) NOT IN (SELECT f3, min(f4) FROM t2);
SELECT * FROM t1 WHERE (2, 0) NOT IN (SELECT f3, min(f4) FROM t2);
EXPLAIN
SELECT * FROM t1 WHERE (2, 0) NOT IN (SELECT f3+f4, min(f4) FROM t2);
SELECT * FROM t1 WHERE (2, 0) NOT IN (SELECT f3+f4, min(f4) FROM t2);
EXPLAIN
SELECT * FROM t1 WHERE (2, 0) NOT IN (SELECT f3, min(f4)+max(f4) FROM t2);
SELECT * FROM t1 WHERE (2, 0) NOT IN (SELECT f3, min(f4)+max(f4) FROM t2);
EXPLAIN
SELECT (2, 0) NOT IN (SELECT f3, min(f4) FROM t2) as not_in;
SELECT (2, 0) NOT IN (SELECT f3, min(f4) FROM t2) as not_in;
EXPLAIN
SELECT * FROM t1 WHERE (2, 0) NOT IN (SELECT f3, count(f4) FROM t2);
SELECT * FROM t1 WHERE (2, 0) NOT IN (SELECT f3, count(f4) FROM t2);
EXPLAIN
SELECT * FROM t1 WHERE (2, 0) NOT IN (SELECT f3, f3 + count(f4) FROM t2);
SELECT * FROM t1 WHERE (2, 0) NOT IN (SELECT f3, f3 + count(f4) FROM t2);
EXPLAIN
SELECT (2, 0) NOT IN (SELECT f3, count(f4) FROM t2) as not_in;
SELECT (2, 0) NOT IN (SELECT f3, count(f4) FROM t2) as not_in;
EXPLAIN
SELECT (2, 0) NOT IN (SELECT f3, count(f4) FROM t2 HAVING max(f4) > 7) as not_in;
SELECT (2, 0) NOT IN (SELECT f3, count(f4) FROM t2 HAVING max(f4) > 7) as not_in;
EXPLAIN
SELECT (2, 0) NOT IN (SELECT f3, count(f4) FROM t2 HAVING max(f4) is null) as not_in;
SELECT (2, 0) NOT IN (SELECT f3, count(f4) FROM t2 HAVING max(f4) is null) as not_in;
EXPLAIN
SELECT (2, 0) NOT IN (SELECT max(f3+f3), count(f4) FROM t2) as not_in;
SELECT (2, 0) NOT IN (SELECT max(f3+f3), count(f4) FROM t2) as not_in;
EXPLAIN
SELECT (2, 0) NOT IN (SELECT max(f3+f3), count(f4)+f3 FROM t2) as not_in;
SELECT (2, 0) NOT IN (SELECT max(f3+f3), count(f4)+f3 FROM t2) as not_in;
EXPLAIN
SELECT * FROM t1 WHERE (2, 0) NOT IN (SELECT min(f3)+f3, min(f4)+f3+max(f4) FROM t2);
SELECT * FROM t1 WHERE (2, 0) NOT IN (SELECT min(f3)+f3, min(f4)+f3+max(f4) FROM t2);
INSERT INTO t1 VALUES (1, 2);
INSERT INTO t1 VALUES (3, 4);
INSERT INTO t2 VALUES (5, 6);
INSERT INTO t2 VALUES (7, 8);
SET @@optimizer_switch = 'materialization=on,semijoin=off';
EXPLAIN
SELECT * FROM t1 WHERE (2, 0) NOT IN (SELECT f3, min(f4) FROM t2 WHERE f3 > 10);
SELECT * FROM t1 WHERE (2, 0) NOT IN (SELECT f3, min(f4) FROM t2 WHERE f3 > 10);
EXPLAIN
SELECT * FROM t1 WHERE (2, 0) NOT IN (SELECT f3+f4, min(f4) FROM t2 WHERE f3 > 10);
SELECT * FROM t1 WHERE (2, 0) NOT IN (SELECT f3+f4, min(f4) FROM t2 WHERE f3 > 10);
EXPLAIN
SELECT * FROM t1 WHERE (2, 0) NOT IN (SELECT f3, min(f4)+max(f4) FROM t2 WHERE f3 > 10);
SELECT * FROM t1 WHERE (2, 0) NOT IN (SELECT f3, min(f4)+max(f4) FROM t2 WHERE f3 > 10);
EXPLAIN
SELECT (2, 0) NOT IN (SELECT f3, min(f4) FROM t2 WHERE f3 > 10) as not_in;
SELECT (2, 0) NOT IN (SELECT f3, min(f4) FROM t2 WHERE f3 > 10) as not_in;
EXPLAIN
SELECT * FROM t1 WHERE (2, 0) NOT IN (SELECT f3, count(f4) FROM t2 WHERE f3 > 10);
SELECT * FROM t1 WHERE (2, 0) NOT IN (SELECT f3, count(f4) FROM t2 WHERE f3 > 10);
EXPLAIN
SELECT * FROM t1 WHERE (2, 0) NOT IN (SELECT f3, f3 + count(f4) FROM t2 WHERE f3 > 10);
SELECT * FROM t1 WHERE (2, 0) NOT IN (SELECT f3, f3 + count(f4) FROM t2 WHERE f3 > 10);
EXPLAIN
SELECT (2, 0) NOT IN (SELECT f3, count(f4) FROM t2 WHERE f3 > 10) as not_in;
SELECT (2, 0) NOT IN (SELECT f3, count(f4) FROM t2 WHERE f3 > 10) as not_in;
EXPLAIN
SELECT (2, 0) NOT IN (SELECT f3, count(f4) FROM t2 WHERE f3 > 10 HAVING max(f4) > 7) as not_in;
SELECT (2, 0) NOT IN (SELECT f3, count(f4) FROM t2 WHERE f3 > 10 HAVING max(f4) > 7) as not_in;
EXPLAIN
SELECT (2, 0) NOT IN (SELECT f3, count(f4) FROM t2 WHERE f3 > 10 HAVING max(f4) is null) as not_in;
SELECT (2, 0) NOT IN (SELECT f3, count(f4) FROM t2 WHERE f3 > 10 HAVING max(f4) is null) as not_in;
EXPLAIN
SELECT (2, 0) NOT IN (SELECT max(f3+f3), count(f4) FROM t2 WHERE f3 > 10) as not_in;
SELECT (2, 0) NOT IN (SELECT max(f3+f3), count(f4) FROM t2 WHERE f3 > 10) as not_in;
EXPLAIN
SELECT (2, 0) NOT IN (SELECT max(f3+f3), count(f4)+f3 FROM t2 WHERE f3 > 10) as not_in;
SELECT (2, 0) NOT IN (SELECT max(f3+f3), count(f4)+f3 FROM t2 WHERE f3 > 10) as not_in;
EXPLAIN
SELECT * FROM t1 WHERE (2, 0) NOT IN (SELECT min(f3)+f3, min(f4)+f3+max(f4) FROM t2 WHERE f3 > 10);
SELECT * FROM t1 WHERE (2, 0) NOT IN (SELECT min(f3)+f3, min(f4)+f3+max(f4) FROM t2 WHERE f3 > 10);
SET @@optimizer_switch = 'materialization=off,semijoin=off';
EXPLAIN
SELECT * FROM t1 WHERE (2, 0) NOT IN (SELECT f3, min(f4) FROM t2 WHERE f3 > 10);
SELECT * FROM t1 WHERE (2, 0) NOT IN (SELECT f3, min(f4) FROM t2 WHERE f3 > 10);
EXPLAIN
SELECT * FROM t1 WHERE (2, 0) NOT IN (SELECT f3+f4, min(f4) FROM t2 WHERE f3 > 10);
SELECT * FROM t1 WHERE (2, 0) NOT IN (SELECT f3+f4, min(f4) FROM t2 WHERE f3 > 10);
EXPLAIN
SELECT * FROM t1 WHERE (2, 0) NOT IN (SELECT f3, min(f4)+max(f4) FROM t2 WHERE f3 > 10);
SELECT * FROM t1 WHERE (2, 0) NOT IN (SELECT f3, min(f4)+max(f4) FROM t2 WHERE f3 > 10);
EXPLAIN
SELECT (2, 0) NOT IN (SELECT f3, min(f4) FROM t2 WHERE f3 > 10) as not_in;
SELECT (2, 0) NOT IN (SELECT f3, min(f4) FROM t2 WHERE f3 > 10) as not_in;
EXPLAIN
SELECT * FROM t1 WHERE (2, 0) NOT IN (SELECT f3, count(f4) FROM t2 WHERE f3 > 10);
SELECT * FROM t1 WHERE (2, 0) NOT IN (SELECT f3, count(f4) FROM t2 WHERE f3 > 10);
EXPLAIN
SELECT * FROM t1 WHERE (2, 0) NOT IN (SELECT f3, f3 + count(f4) FROM t2 WHERE f3 > 10);
SELECT * FROM t1 WHERE (2, 0) NOT IN (SELECT f3, f3 + count(f4) FROM t2 WHERE f3 > 10);
EXPLAIN
SELECT (2, 0) NOT IN (SELECT f3, count(f4) FROM t2 WHERE f3 > 10) as not_in;
SELECT (2, 0) NOT IN (SELECT f3, count(f4) FROM t2 WHERE f3 > 10) as not_in;
EXPLAIN
SELECT (2, 0) NOT IN (SELECT f3, count(f4) FROM t2 WHERE f3 > 10 HAVING max(f4) > 7) as not_in;
SELECT (2, 0) NOT IN (SELECT f3, count(f4) FROM t2 WHERE f3 > 10 HAVING max(f4) > 7) as not_in;
EXPLAIN
SELECT (2, 0) NOT IN (SELECT f3, count(f4) FROM t2 WHERE f3 > 10 HAVING max(f4) is null) as not_in;
SELECT (2, 0) NOT IN (SELECT f3, count(f4) FROM t2 WHERE f3 > 10 HAVING max(f4) is null) as not_in;
EXPLAIN
SELECT (2, 0) NOT IN (SELECT max(f3+f3), count(f4) FROM t2 WHERE f3 > 10) as not_in;
SELECT (2, 0) NOT IN (SELECT max(f3+f3), count(f4) FROM t2 WHERE f3 > 10) as not_in;
EXPLAIN
SELECT (2, 0) NOT IN (SELECT max(f3+f3), count(f4)+f3 FROM t2 WHERE f3 > 10) as not_in;
SELECT (2, 0) NOT IN (SELECT max(f3+f3), count(f4)+f3 FROM t2 WHERE f3 > 10) as not_in;
EXPLAIN
SELECT * FROM t1 WHERE (2, 0) NOT IN (SELECT min(f3)+f3, min(f4)+f3+max(f4) FROM t2 WHERE f3 > 10);
SELECT * FROM t1 WHERE (2, 0) NOT IN (SELECT min(f3)+f3, min(f4)+f3+max(f4) FROM t2 WHERE f3 > 10);
set @@optimizer_switch=@save_optimizer_switch;
drop table t1,t2;
sql/item.cc
View file @ ec239491
......@@ -382,7 +382,7 @@ Item::Item():
collation(&my_charset_bin, DERIVATION_COERCIBLE)
{
marker= 0;
maybe_null=null_value=with_sum_func=unsigned_flag=0;
maybe_null=null_value=with_sum_func=with_field=unsigned_flag=0;
in_rollup= 0;
decimals= 0; max_length= 0;
with_subselect= 0;
......@@ -429,6 +429,7 @@ Item::Item(THD *thd, Item *item):
null_value(item->null_value),
unsigned_flag(item->unsigned_flag),
with_sum_func(item->with_sum_func),
with_field(item->with_field),
fixed(item->fixed),
is_autogenerated_name(item->is_autogenerated_name),
with_subselect(item->with_subselect),
......@@ -1890,6 +1891,7 @@ Item_field::Item_field(Field *f)
if this item is to be reused
*/
orig_table_name= orig_field_name= "";
with_field= 1;
}
......@@ -1938,6 +1940,7 @@ Item_field::Item_field(THD *thd, Name_resolution_context *context_arg,
name= (char*) orig_field_name;
}
set_field(f);
with_field= 1;
}
......@@ -1952,6 +1955,7 @@ Item_field::Item_field(Name_resolution_context *context_arg,
collation.set(DERIVATION_IMPLICIT);
if (select && select->parsing_place != IN_HAVING)
select->select_n_where_fields++;
with_field= 1;
}
/**
......@@ -1968,6 +1972,7 @@ Item_field::Item_field(THD *thd, Item_field *item)
any_privileges(item->any_privileges)
{
collation.set(DERIVATION_IMPLICIT);
with_field= 1;
}
void Item_field::set_field(Field *field_par)
......@@ -6285,6 +6290,7 @@ void Item_ref::set_properties()
split_sum_func() doesn't try to change the reference.
*/
with_sum_func= (*ref)->with_sum_func;
with_field= (*ref)->with_field;
unsigned_flag= (*ref)->unsigned_flag;
fixed= 1;
if (alias_name_used)
......@@ -6709,6 +6715,7 @@ Item_cache_wrapper::Item_cache_wrapper(Item *item_arg)
decimals= orig_item->decimals;
collation.set(orig_item->collation);
with_sum_func= orig_item->with_sum_func;
with_field= orig_item->with_field;
unsigned_flag= orig_item->unsigned_flag;
name= item_arg->name;
name_length= item_arg->name_length;
......
sql/item.h
View file @ ec239491
......@@ -544,7 +544,11 @@ public:
of a query with ROLLUP */
bool null_value; /* if item is null */
bool unsigned_flag;
bool with_sum_func;
bool with_sum_func; /* True if item contains a sum func */
/**
True if any item except Item_sum_func contains a field. Set during parsing.
*/
bool with_field;
bool fixed; /* If item fixed with fix_fields */
bool is_autogenerated_name; /* indicate was name of this Item
autogenerated or set by user */
......
sql/item_cmpfunc.cc
View file @ ec239491
......@@ -1741,6 +1741,7 @@ bool Item_in_optimizer::fix_left(THD *thd, Item **ref)
}
not_null_tables_cache= args[0]->not_null_tables();
with_sum_func= args[0]->with_sum_func;
with_field= args[0]->with_field;
if ((const_item_cache= args[0]->const_item()))
cache->store(args[0]);
return 0;
......@@ -1766,6 +1767,7 @@ bool Item_in_optimizer::fix_fields(THD *thd, Item **ref)
if (args[1]->maybe_null)
maybe_null=1;
with_sum_func= with_sum_func || args[1]->with_sum_func;
with_field= with_field || args[1]->with_field;
used_tables_cache|= args[1]->used_tables();
not_null_tables_cache|= args[1]->not_null_tables();
const_item_cache&= args[1]->const_item();
......@@ -2228,6 +2230,7 @@ void Item_func_interval::fix_length_and_dec()
used_tables_cache|= row->used_tables();
not_null_tables_cache= row->not_null_tables();
with_sum_func= with_sum_func || row->with_sum_func;
with_field= with_field || row->with_field;
const_item_cache&= row->const_item();
}
......@@ -4380,6 +4383,7 @@ Item_cond::fix_fields(THD *thd, Item **ref)
const_item_cache= FALSE;
}
with_sum_func= with_sum_func || item->with_sum_func;
with_field= with_field || item->with_field;
with_subselect|= item->with_subselect;
if (item->maybe_null)
maybe_null=1;
......@@ -5035,6 +5039,7 @@ Item_func_regex::fix_fields(THD *thd, Item **ref)
args[1]->fix_fields(thd, args + 1)) || args[1]->check_cols(1))
return TRUE; /* purecov: inspected */
with_sum_func=args[0]->with_sum_func || args[1]->with_sum_func;
with_field= args[0]->with_field || args[1]->with_field;
max_length= 1;
decimals= 0;
......
sql/item_func.cc
View file @ ec239491
......@@ -79,6 +79,7 @@ void Item_func::set_arguments(List<Item> &list)
{
*(save_args++)= item;
with_sum_func|=item->with_sum_func;
with_field|= item->with_field;
}
}
list.empty(); // Fields are used
......@@ -129,6 +130,7 @@ Item_func::Item_func(THD *thd, Item_func *item)
Sets as a side effect the following class variables:
maybe_null Set if any argument may return NULL
with_sum_func Set if any of the arguments contains a sum function
with_field Set if any of the arguments contains or is a field
used_tables_cache Set to union of the tables used by arguments
str_value.charset If this is a string function, set this to the
......@@ -198,6 +200,7 @@ Item_func::fix_fields(THD *thd, Item **ref)
maybe_null=1;
with_sum_func= with_sum_func || item->with_sum_func;
with_field= with_field || item->with_field;
used_tables_cache|= item->used_tables();
not_null_tables_cache|= item->not_null_tables();
const_item_cache&= item->const_item();
......@@ -2939,6 +2942,7 @@ udf_handler::fix_fields(THD *thd, Item_result_field *func,
if (item->maybe_null)
func->maybe_null=1;
func->with_sum_func= func->with_sum_func || item->with_sum_func;
func->with_field= func->with_field || item->with_field;
used_tables_cache|=item->used_tables();
const_item_cache&=item->const_item();
f_args.arg_type[i]=item->result_type();
......
sql/item_func.h
View file @ ec239491
......@@ -64,6 +64,7 @@ public:
allowed_arg_cols(1), arg_count(0)
{
with_sum_func= 0;
with_field= 0;
}
Item_func(Item *a):
allowed_arg_cols(1), arg_count(1)
......@@ -71,6 +72,7 @@ public:
args= tmp_arg;
args[0]= a;
with_sum_func= a->with_sum_func;
with_field= a->with_field;
}
Item_func(Item *a,Item *b):
allowed_arg_cols(1), arg_count(2)
......@@ -78,6 +80,7 @@ public:
args= tmp_arg;
args[0]= a; args[1]= b;
with_sum_func= a->with_sum_func || b->with_sum_func;
with_field= a->with_field || b->with_field;
}
Item_func(Item *a,Item *b,Item *c):
allowed_arg_cols(1)
......@@ -88,6 +91,7 @@ public:
arg_count= 3;
args[0]= a; args[1]= b; args[2]= c;
with_sum_func= a->with_sum_func || b->with_sum_func || c->with_sum_func;
with_field= a->with_field || b->with_field || c->with_field;
}
}
Item_func(Item *a,Item *b,Item *c,Item *d):
......@@ -100,6 +104,8 @@ public:
args[0]= a; args[1]= b; args[2]= c; args[3]= d;
with_sum_func= a->with_sum_func || b->with_sum_func ||
c->with_sum_func || d->with_sum_func;
with_field= a->with_field || b->with_field ||
c->with_field || d->with_field;
}
}
Item_func(Item *a,Item *b,Item *c,Item *d,Item* e):
......@@ -111,6 +117,8 @@ public:
args[0]= a; args[1]= b; args[2]= c; args[3]= d; args[4]= e;
with_sum_func= a->with_sum_func || b->with_sum_func ||
c->with_sum_func || d->with_sum_func || e->with_sum_func ;
with_field= a->with_field || b->with_field ||
c->with_field || d->with_field || e->with_field;
}
}
Item_func(List<Item> &list);
......
sql/item_row.cc
View file @ ec239491
......@@ -86,6 +86,7 @@ bool Item_row::fix_fields(THD *thd, Item **ref)
}
maybe_null|= item->maybe_null;
with_sum_func= with_sum_func || item->with_sum_func;
with_field= with_field || item->with_field;
}
fixed= 1;
return FALSE;
......
sql/item_strfunc.cc
View file @ ec239491
......@@ -2248,6 +2248,7 @@ void Item_func_make_set::fix_length_and_dec()
not_null_tables_cache&= item->not_null_tables();
const_item_cache&= item->const_item();
with_sum_func= with_sum_func || item->with_sum_func;
with_field= with_field || item->with_field;
}
......
sql/item_sum.cc
View file @ ec239491
......@@ -415,6 +415,7 @@ void Item_sum::mark_as_sum_func()
cur_select->n_sum_items++;
cur_select->with_sum_func= 1;
with_sum_func= 1;
with_field= 0;
}
......
sql/sql_select.cc
View file @ ec239491
......@@ -517,12 +517,49 @@ JOIN::prepare(Item ***rref_pointer_array,
tables_list, &select_lex->leaf_tables,
FALSE, SELECT_ACL, SELECT_ACL))
DBUG_RETURN(-1);
/*
TRUE if the SELECT list mixes elements with and without grouping,
and there is no GROUP BY clause. Mixing non-aggregated fields with
aggregate functions in the SELECT list is a MySQL exptenstion that
is allowed only if the ONLY_FULL_GROUP_BY sql mode is not set.
*/
bool mixed_implicit_grouping= false;
if ((~thd->variables.sql_mode & MODE_ONLY_FULL_GROUP_BY) &&
select_lex->with_sum_func && !group_list)
{
List_iterator_fast <Item> select_it(fields_list);
Item *select_el; /* Element of the SELECT clause, can be an expression. */
bool found_field_elem= false;
bool found_sum_func_elem= false;
while ((select_el= select_it++))
{
if (select_el->with_sum_func)
found_sum_func_elem= true;
if (select_el->with_field)
found_field_elem= true;
if (found_sum_func_elem && found_field_elem)
{
mixed_implicit_grouping= true;
break;
}
}
}
TABLE_LIST *table_ptr;
for (table_ptr= select_lex->leaf_tables;
for (TABLE_LIST *table_ptr= select_lex->leaf_tables;
table_ptr;
table_ptr= table_ptr->next_leaf)
tables++;
{
tables++; /* Count the number of tables in the join. */
/*
If the query uses implicit grouping where the select list contains both
aggregate functions and non-aggregate fields, any non-aggregated field
may produce a NULL value. Set all fields of each table as nullable before
semantic analysis to take into account this change of nullability.
*/
if (mixed_implicit_grouping)
table_ptr->table->maybe_null= 1;
}
if (setup_wild(thd, tables_list, fields_list, &all_fields, wild_num) ||
select_lex->setup_ref_array(thd, og_num) ||
......
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