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Commit a32b868c authored by unknown's avatar unknown
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subselect transformation moved in after-fix_field place 

removed "of is null" if it is possible
  (this cset should be SCRUM related, but not approved as scrum task yet)


mysql-test/r/subselect.result:
  new subselect test result (new place of error detecting & and more subselect reducing)
sql/item.cc:
  layout fix
sql/item.h:
  unneed ';'
  fixed print pethod
sql/item_cmpfunc.cc:
  new method to support transformation after fix_fields
sql/item_cmpfunc.h:
  new method to support transformation after fix_fields
  fixed Item printing
sql/item_subselect.cc:
  new transformation
sql/item_subselect.h:
  new transformation
sql/sql_derived.cc:
  'table' & 'table_list' now is not union
sql/sql_lex.cc:
  'table' & 'table_list' now is not union to support reinit only shared tables (but all)
sql/sql_lex.h:
  mark fake st_select_lex
sql/sql_olap.cc:
  fixed table assignment
  TODO added
sql/sql_select.cc:
  'table' & 'table_list' now is not union
  transforming subselect
sql/sql_union.cc:
  prepare make on fix_fields
sql/sql_yacc.yy:
  fixed layout
sql/table.h:
  'table & 'table_list' now is different fields
parent 79c53934
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Showing with 430 additions and 302 deletions
mysql-test/r/subselect.result
View file @ a32b868c
......@@ -46,7 +46,7 @@ SELECT 1 FROM (SELECT 1 as a) as b HAVING (SELECT a)=1;
1
1
SELECT (SELECT 1), a;
Unknown column 'a' in 'field list'
Unknown column 'a' in 'checking transformed subquery'
SELECT 1 as a FROM (SELECT 1) as b HAVING (SELECT a)=1;
a
1
......@@ -668,7 +668,6 @@ id
EXPLAIN SELECT * FROM t2 WHERE id IN (SELECT 1+(select 1));
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t2 ref id id 5 const 1 Using where; Using index
3 SUBQUERY NULL NULL NULL NULL NULL NULL NULL No tables used
Warnings:
Note 1247 Select 3 was reduced during optimisation
Note 1247 Select 2 was reduced during optimisation
......@@ -1008,7 +1007,7 @@ CREATE TABLE t1 SELECT (SELECT 1 as a UNION SELECT 1+1 limit 1,1) as a;
SHOW CREATE TABLE t1;
Table Create Table
t1 CREATE TABLE `t1` (
`a` bigint(1) NOT NULL default '0'
`a` bigint(17) NOT NULL default '0'
) TYPE=MyISAM CHARSET=latin1
drop table t1;
create table t1 (a int);
......
sql/item.cc
View file @ a32b868c
......@@ -1324,17 +1324,15 @@ bool Item_ref::fix_fields(THD *thd,TABLE_LIST *tables, Item **reference)
}
}
/*
* The following conditional is changed as to correctly identify
* incorrect references in group functions or forward references
* with sub-select's / derived tables, while it prevents this
* check when Item_ref is created in an expression involving
* summing function, which is to be placed in the user variable.
*
*/
/*
The following conditional is changed as to correctly identify
incorrect references in group functions or forward references
with sub-select's / derived tables, while it prevents this
check when Item_ref is created in an expression involving
summing function, which is to be placed in the user variable.
*/
if (((*ref)->with_sum_func && name &&
(depended_from ||
(depended_from ||
!(thd->lex.current_select->linkage != GLOBAL_OPTIONS_TYPE &&
thd->lex.current_select->select_lex()->having_fix_field))) ||
!(*ref)->fixed)
......
sql/item.h
View file @ a32b868c
......@@ -100,7 +100,7 @@ public:
virtual bool get_time(TIME *ltime);
virtual bool get_date_result(TIME *ltime,bool fuzzydate)
{ return get_date(ltime,fuzzydate); }
virtual bool is_null() { return 0; };
virtual bool is_null() { return 0; }
virtual void top_level_item() {}
virtual void set_result_field(Field *field) {}
virtual bool is_result_field() { return 0; }
......@@ -560,6 +560,15 @@ public:
longlong val_int();
String* val_str(String* s);
bool get_date(TIME *ltime, bool fuzzydate);
void print(String *str)
{
str->append("ref_null_helper(");
if (ref && *ref)
(*ref)->print(str);
else
str->append('?');
str->append(')');
}
};
......@@ -605,6 +614,15 @@ public:
{}
bool fix_fields(THD *, struct st_table_list *, Item ** ref);
Item **storage() {return &item;}
void print(String *str)
{
str->append("ref_null_helper('");
if (item)
item->print(str);
else
str->append('?');
str->append(')');
}
};
/*
......
sql/item_cmpfunc.cc
View file @ a32b868c
......@@ -318,16 +318,24 @@ int Arg_comparator::compare_e_row()
return 1;
}
bool Item_in_optimizer::preallocate_row()
bool Item_in_optimizer::fix_left(THD *thd,
struct st_table_list *tables,
Item **ref)
{
return (!(cache= Item_cache::get_cache(ROW_RESULT)));
if (args[0]->fix_fields(thd, tables, ref) ||
(!cache && !(cache= Item_cache::get_cache(args[0]->result_type()))))
return 1;
cache->setup(args[0]);
return 0;
}
bool Item_in_optimizer::fix_fields(THD *thd, struct st_table_list *tables,
Item ** ref)
{
if (args[0]->fix_fields(thd, tables, args))
if (fix_left(thd, tables, ref))
return 1;
if (args[0]->maybe_null)
maybe_null=1;
......@@ -340,9 +348,6 @@ bool Item_in_optimizer::fix_fields(THD *thd, struct st_table_list *tables,
with_sum_func= args[0]->with_sum_func;
used_tables_cache= args[0]->used_tables();
const_item_cache= args[0]->const_item();
if (!cache && !(cache= Item_cache::get_cache(args[0]->result_type())))
return 1;
cache->setup(args[0]);
if (cache->cols() == 1)
{
if (args[0]->used_tables())
......@@ -361,7 +366,7 @@ bool Item_in_optimizer::fix_fields(THD *thd, struct st_table_list *tables,
((Item_cache *)cache->el(i))->set_used_tables(0);
}
}
if (args[1]->fix_fields(thd, tables, args))
if (!args[1]->fixed && args[1]->fix_fields(thd, tables, args))
return 1;
Item_in_subselect * sub= (Item_in_subselect *)args[1];
if (args[0]->cols() != sub->engine->cols())
......@@ -1592,7 +1597,8 @@ Item_cond::fix_fields(THD *thd, TABLE_LIST *tables, Item **ref)
}
if (abort_on_null)
item->top_level_item();
if (item->fix_fields(thd, tables, li.ref()) || item->check_cols(1))
if ((!item->fixed &&
item->fix_fields(thd, tables, li.ref())) || item->check_cols(1))
return 1; /* purecov: inspected */
used_tables_cache|=item->used_tables();
with_sum_func= with_sum_func || item->with_sum_func;
......
sql/item_cmpfunc.h
View file @ a32b868c
......@@ -91,9 +91,8 @@ protected:
public:
Item_in_optimizer(Item *a, Item_in_subselect *b):
Item_bool_func(a, (Item *)b), cache(0) {}
// used by row in transformer
bool preallocate_row();
bool fix_fields(THD *, struct st_table_list *, Item **);
bool fix_left(THD *thd, struct st_table_list *tables, Item **ref);
bool is_null();
/*
Item_in_optimizer item is special boolean function. On value request
......@@ -103,7 +102,7 @@ public:
Item_in_optimizer return NULL, else it evaluate Item_in_subselect.
*/
longlong val_int();
const char *func_name() const { return "IN_OPTIMIZER"; }
Item_cache **get_cache() { return &cache; }
};
......
sql/item_subselect.cc
View file @ a32b868c
......@@ -56,7 +56,6 @@ void Item_subselect::init(THD *thd, st_select_lex *select_lex,
DBUG_ENTER("Item_subselect::init");
DBUG_PRINT("subs", ("select_lex 0x%xl", (ulong) select_lex));
select_transformer(thd, select_lex->master_unit());
if (select_lex->next_select())
engine= new subselect_union_engine(thd, select_lex->master_unit(), result,
this);
......@@ -72,36 +71,39 @@ Item_subselect::~Item_subselect()
delete engine;
}
void Item_subselect::select_transformer(THD *thd, st_select_lex_unit *unit)
Item_subselect::trans_res
Item_subselect::select_transformer(THD *thd,
JOIN *join)
{
DBUG_ENTER("Item_subselect::select_transformer");
DBUG_VOID_RETURN;
DBUG_RETURN(OK);
}
bool Item_subselect::fix_fields(THD *thd, TABLE_LIST *tables, Item **ref)
{
if (substitution)
{
(*ref)= substitution;
substitution->name= name;
if (have_to_be_excluded)
engine->exclude();
substitution= 0;
int ret= (*ref)->fix_fields(thd, tables, ref);
// We can't substitute aggregate functions (like (SELECT (max(i)))
if ((*ref)->with_sum_func)
{
my_error(ER_INVALID_GROUP_FUNC_USE, MYF(0));
return 1;
}
return ret;
}
char const *save_where= thd->where;
int res= engine->prepare();
if (!res)
{
if (substitution)
{
(*ref)= substitution;
substitution->name= name;
if (have_to_be_excluded)
engine->exclude();
substitution= 0;
fixed= 1;
thd->where= "checking transformed subquery";
int ret= (*ref)->fix_fields(thd, tables, ref);
// We can't substitute aggregate functions (like (SELECT (max(i)))
if ((*ref)->with_sum_func)
{
my_error(ER_INVALID_GROUP_FUNC_USE, MYF(0));
return 1;
}
return ret;
}
// Is it one field subselect?
if (engine->cols() > max_columns)
{
......@@ -150,12 +152,14 @@ void Item_singlerow_subselect::reset()
value->null_value= 1;
}
void Item_singlerow_subselect::select_transformer(THD *thd,
st_select_lex_unit *unit)
Item_subselect::trans_res
Item_singlerow_subselect::select_transformer(THD *thd,
JOIN *join)
{
SELECT_LEX *select_lex= unit->first_select();
SELECT_LEX *select_lex= join->select_lex;
if (!select_lex->next_select() && !select_lex->table_list.elements &&
if (!select_lex->master_unit()->first_select()->next_select() &&
!select_lex->table_list.elements &&
select_lex->item_list.elements == 1 &&
/*
We cant change name of Item_field or Item_ref, because it will
......@@ -183,18 +187,20 @@ void Item_singlerow_subselect::select_transformer(THD *thd,
if (select_lex->where || select_lex->having)
{
Item *cond;
if (!select_lex->having)
cond= select_lex->where;
else if (!select_lex->where)
cond= select_lex->having;
if (!join->having)
cond= join->conds;
else if (!join->conds)
cond= join->having;
else
if (!(cond= new Item_cond_and(select_lex->having, select_lex->where)))
return;
if (!(cond= new Item_cond_and(join->conds, join->having)))
return ERROR;
if (!(substitution= new Item_func_if(cond, substitution,
new Item_null())))
return;
return ERROR;
}
return REDUCE;
}
return OK;
}
void Item_singlerow_subselect::store(uint i, Item *item)
......@@ -313,6 +319,37 @@ Item_exists_subselect::Item_exists_subselect(THD *thd,
DBUG_VOID_RETURN;
}
bool Item_in_subselect::test_limit(SELECT_LEX_UNIT *unit)
{
SELECT_LEX_NODE *global= unit->global_parameters;
if (global->select_limit != HA_POS_ERROR)
{
my_error(ER_NOT_SUPPORTED_YET, MYF(0),
"LIMIT & IN/ALL/ANY/SOME subquery");
return(1);
}
SELECT_LEX *sl= unit->first_select();
for (; sl; sl= sl->next_select())
{
if (sl->select_limit != HA_POS_ERROR)
{
my_error(ER_NOT_SUPPORTED_YET, MYF(0),
"LIMIT & IN/ALL/ANY/SOME subquery");
return(1);
}
// We need only 1 row to determinate existence
sl->select_limit= 1;
// no sense in ORDER BY without LIMIT
sl->order_list.empty();
}
// no sense in ORDER BY without LIMIT
global->order_list.empty();
// We need only 1 row to determinate existence
global->select_limit= 1;
return(0);
}
Item_in_subselect::Item_in_subselect(THD *thd, Item * left_exp,
st_select_lex *select_lex):
Item_exists_subselect()
......@@ -322,25 +359,25 @@ Item_in_subselect::Item_in_subselect(THD *thd, Item * left_exp,
init(thd, select_lex, new select_exists_subselect(this));
max_columns= UINT_MAX;
maybe_null= 1;
abort_on_null= 0;
reset();
// We need only 1 row to determinate existence
select_lex->master_unit()->global_parameters->select_limit= 1;
test_limit(select_lex->master_unit());
DBUG_VOID_RETURN;
}
Item_allany_subselect::Item_allany_subselect(THD *thd, Item * left_exp,
compare_func_creator f,
compare_func_creator fn,
st_select_lex *select_lex):
Item_in_subselect()
{
DBUG_ENTER("Item_in_subselect::Item_in_subselect");
left_expr= left_exp;
func= f;
func= fn;
init(thd, select_lex, new select_exists_subselect(this));
max_columns= 1;
abort_on_null= 0;
reset();
// We need only 1 row to determinate existence
select_lex->master_unit()->global_parameters->select_limit= 1;
test_limit(select_lex->master_unit());
DBUG_VOID_RETURN;
}
......@@ -430,6 +467,7 @@ Item_in_subselect::Item_in_subselect(Item_in_subselect *item):
Item_exists_subselect(item)
{
left_expr= item->left_expr;
abort_on_null= item->abort_on_null;
}
Item_allany_subselect::Item_allany_subselect(Item_allany_subselect *item):
......@@ -438,227 +476,258 @@ Item_allany_subselect::Item_allany_subselect(Item_allany_subselect *item):
func= item->func;
}
void Item_in_subselect::single_value_transformer(THD *thd,
st_select_lex_unit *unit,
Item *left_expr,
compare_func_creator func)
Item_subselect::trans_res
Item_in_subselect::single_value_transformer(THD *thd,
JOIN *join,
Item *left_expr,
compare_func_creator func)
{
DBUG_ENTER("Item_in_subselect::single_value_transformer");
if (unit->global_parameters->select_limit != HA_POS_ERROR)
{
my_error(ER_NOT_SUPPORTED_YET, MYF(0),
"LIMIT & IN/ALL/ANY/SOME subquery");
DBUG_VOID_RETURN;
}
// no sense in ORDER BY without LIMIT
unit->global_parameters->order_list.empty();
SELECT_LEX *select_lex= join->select_lex;
Item_in_optimizer *optimizer;
substitution= optimizer= new Item_in_optimizer(left_expr, this);
if (!optimizer)
DBUG_VOID_RETURN;
thd->where= "scalar IN/ALL/ANY subquery";
/*
As far as Item_ref_in_optimizer do not substitude itself on fix_fields
we can use same item for all selects.
*/
Item *expr= new Item_ref((Item**)optimizer->get_cache(),
(char *)"<no matter>",
(char*)"<left expr>");
unit->dependent= 1;
for (SELECT_LEX * sl= unit->first_select(); sl; sl= sl->next_select())
if (!substitution)
{
if (sl->select_limit != HA_POS_ERROR)
//first call for this unit
SELECT_LEX_UNIT *unit= select_lex->master_unit();
substitution= optimizer= new Item_in_optimizer(left_expr, this);
SELECT_LEX_NODE *current= thd->lex.current_select, *up;
thd->lex.current_select= up= current->return_after_parsing();
//optimizer never use Item **ref => we can pass 0 as parameter
if (!optimizer || optimizer->fix_left(thd, up->get_table_list(), 0))
{
my_error(ER_NOT_SUPPORTED_YET, MYF(0),
"LIMIT & IN/ALL/ANY/SOME subquery");
DBUG_VOID_RETURN;
thd->lex.current_select= current;
DBUG_RETURN(ERROR);
}
thd->lex.current_select= current;
sl->dependent= 1;
Item *item;
if (sl->item_list.elements > 1)
{
my_error(ER_CARDINALITY_COL, MYF(0), 1);
DBUG_VOID_RETURN;
}
else
item= (Item*) sl->item_list.pop();
/*
As far as Item_ref_in_optimizer do not substitude itself on fix_fields
we can use same item for all selects.
*/
expr= new Item_ref((Item**)optimizer->get_cache(),
(char *)"<no matter>",
(char *)"<left expr>");
sl->order_list.empty(); // no sense in ORDER BY without LIMIT
unit->dependent= 1;
}
if (sl->having || sl->with_sum_func || sl->group_list.elements)
select_lex->dependent= 1;
Item *item;
if (select_lex->item_list.elements > 1)
{
my_error(ER_CARDINALITY_COL, MYF(0), 1);
DBUG_RETURN(ERROR);
}
else
item= (Item*) select_lex->item_list.head();
if (join->having || select_lex->with_sum_func ||
select_lex->group_list.elements)
{
item= (*func)(expr,
new Item_ref_null_helper(this,
select_lex->ref_pointer_array,
(char *)"<ref>",
this->full_name()));
join->having= and_items(join->having, item);
select_lex->having_fix_field= 1;
if (join->having->fix_fields(thd, join->tables_list, &join->having))
{
sl->item_list.push_back(item);
setup_ref_array(thd, &sl->ref_pointer_array,
1 + sl->with_sum_func +
sl->order_list.elements + sl->group_list.elements);
// To prevent crash on Item_ref_null_helper destruction in case of error
sl->ref_pointer_array[0]= 0;
item= (*func)(expr, new Item_ref_null_helper(this,
sl->ref_pointer_array,
(char *)"<ref>",
this->full_name()));
sl->having= and_items(sl->having, item);
select_lex->having_fix_field= 0;
DBUG_RETURN(ERROR);
}
else
select_lex->having_fix_field= 0;
}
else
{
select_lex->item_list.empty();
select_lex->item_list.push_back(new Item_int("Not_used",
(longlong) 1, 21));
select_lex->ref_pointer_array[0]= select_lex->item_list.head();
if (select_lex->table_list.elements)
{
sl->item_list.empty();
sl->item_list.push_back(new Item_int("Not_used", (longlong) 1, 21));
if (sl->table_list.elements)
Item *having= item, *isnull= item;
if (item->type() == Item::FIELD_ITEM &&
((Item_field*) item)->field_name[0] == '*')
{
Item *having= item, *isnull= item;
if (item->type() == Item::FIELD_ITEM &&
((Item_field*) item)->field_name[0] == '*')
Item_asterisk_remover *remover;
item= remover= new Item_asterisk_remover(this, item,
(char *)"<no matter>",
(char *)"<result>");
if (!abort_on_null)
{
Item_asterisk_remover *remover;
item= remover= new Item_asterisk_remover(this, item,
(char*)"<no matter>",
(char*)"<result>");
having=
new Item_is_not_null_test(this,
new Item_ref(remover->storage(),
(char*)"<no matter>",
(char*)"<null test>"));
(char *)"<no matter>",
(char *)"<null test>"));
isnull=
new Item_is_not_null_test(this,
new Item_ref(remover->storage(),
(char*)"<no matter>",
(char*)"<null test>"));
(char *)"<no matter>",
(char *)"<null test>"));
}
having= new Item_is_not_null_test(this, having);
sl->having= (sl->having ?
new Item_cond_and(having, sl->having) :
having);
item= new Item_cond_or((*func)(expr, item),
new Item_func_isnull(isnull));
sl->where= and_items(sl->where, item);
}
else
item= (*func)(expr, item);
if (!abort_on_null)
{
if (item->type() == Item::FIELD_ITEM &&
((Item_field*) item)->field_name[0] == '*')
having= new Item_is_not_null_test(this, having);
join->having= (join->having ?
new Item_cond_and(having, join->having) :
having);
select_lex->having_fix_field= 1;
if (join->having->fix_fields(thd, join->tables_list, &join->having))
{
my_error(ER_NO_TABLES_USED, MYF(0));
DBUG_VOID_RETURN;
select_lex->having_fix_field= 0;
DBUG_RETURN(ERROR);
}
if (unit->first_select()->next_select())
{
/*
It is in union => we should perform it.
Item_asterisk_remover used only as wrapper to receine NULL value
*/
sl->having= (*func)(expr,
select_lex->having_fix_field= 0;
item= new Item_cond_or(item,
new Item_func_isnull(isnull));
}
join->conds= and_items(join->conds, item);
if (join->conds->fix_fields(thd, join->tables_list, &join->conds))
DBUG_RETURN(ERROR);
}
else
{
if (item->type() == Item::FIELD_ITEM &&
((Item_field*) item)->field_name[0] == '*')
{
my_error(ER_NO_TABLES_USED, MYF(0));
DBUG_RETURN(ERROR);
}
if (select_lex->master_unit()->first_select()->next_select())
{
/*
It is in union => we should perform it.
Item_asterisk_remover used only as wrapper to receine NULL value
*/
join->having= (*func)(expr,
new Item_asterisk_remover(this, item,
(char *)"<no matter>",
(char*)"<result>"));
(char *)"<result>"));
select_lex->having_fix_field= 1;
if (join->having->fix_fields(thd, join->tables_list, &join->having))
{
select_lex->having_fix_field= 0;
DBUG_RETURN(ERROR);
}
else
select_lex->having_fix_field= 0;
}
else
{
// it is single select without tables => possible optimization
item= (*func)(left_expr, item);
// fix_field of item will be done in time of substituting
substitution= item;
have_to_be_excluded= 1;
if (thd->lex.describe)
{
// it is single select without tables => possible optimization
item= (*func)(left_expr, item);
substitution= item;
have_to_be_excluded= 1;
if (thd->lex.describe)
{
char warn_buff[MYSQL_ERRMSG_SIZE];
sprintf(warn_buff, ER(ER_SELECT_REDUCED), sl->select_number);
push_warning(thd, MYSQL_ERROR::WARN_LEVEL_NOTE,
ER_SELECT_REDUCED, warn_buff);
}
char warn_buff[MYSQL_ERRMSG_SIZE];
sprintf(warn_buff, ER(ER_SELECT_REDUCED), select_lex->select_number);
push_warning(thd, MYSQL_ERROR::WARN_LEVEL_NOTE,
ER_SELECT_REDUCED, warn_buff);
}
DBUG_RETURN(REDUCE);
}
}
}
DBUG_VOID_RETURN;
DBUG_RETURN(OK);
}
void Item_in_subselect::row_value_transformer(THD *thd,
st_select_lex_unit *unit,
Item_subselect::trans_res
Item_in_subselect::row_value_transformer(THD *thd,
JOIN *join,
Item *left_expr)
{
DBUG_ENTER("Item_in_subselect::row_value_transformer");
if (unit->global_parameters->select_limit !=
HA_POS_ERROR)
{
/*
Because we do the following (not exactly, following is just explenation)
transformation
SELECT * from t1 WHERE t1.a IN (SELECT t2.a FROM t2)
->
SELECT * from t1 WHERE EXISTS(SELECT 1 FROM t2 t1.a = t2.a LIMIT 1)
it's impossible to support limit in the sub select.
*/
my_error(ER_NOT_SUPPORTED_YET, MYF(0),
"LIMIT & IN/ALL/ANY/SOME subquery");
DBUG_VOID_RETURN;
}
// no sense in ORDER BY without LIMIT
unit->global_parameters->order_list.empty();
thd->where= "row IN/ALL/ANY subquery";
Item_in_optimizer *optimizer;
substitution= optimizer= new Item_in_optimizer(left_expr, this);
if (!optimizer)
DBUG_VOID_RETURN;
SELECT_LEX *select_lex= join->select_lex;
unit->dependent= 1;
uint n= left_expr->cols();
if (optimizer->preallocate_row() || (*optimizer->get_cache())->allocate(n))
DBUG_VOID_RETURN;
for (SELECT_LEX * sl= unit->first_select(); sl; sl= sl->next_select())
if (!substitution)
{
if (sl->select_limit != HA_POS_ERROR)
//first call for this unit
SELECT_LEX_UNIT *unit= select_lex->master_unit();
substitution= optimizer= new Item_in_optimizer(left_expr, this);
SELECT_LEX_NODE *current= thd->lex.current_select, *up;
thd->lex.current_select= up= current->return_after_parsing();
//optimizer never use Item **ref => we can pass 0 as parameter
if (!optimizer || optimizer->fix_left(thd, up->get_table_list(), 0))
{
my_error(ER_NOT_SUPPORTED_YET, MYF(0),
"LIMIT & IN/ALL/ANY/SOME subquery");
DBUG_VOID_RETURN;
thd->lex.current_select= current;
DBUG_RETURN(ERROR);
}
sl->order_list.empty(); // no sense in ORDER BY without LIMIT
thd->lex.current_select= current;
unit->dependent= 1;
}
uint n= left_expr->cols();
sl->dependent= 1;
select_lex->dependent= 1;
Item *item= 0;
List_iterator_fast<Item> li(sl->item_list);
for (uint i= 0; i < n; i++)
Item *item= 0;
List_iterator_fast<Item> li(select_lex->item_list);
for (uint i= 0; i < n; i++)
{
Item *func=
new Item_ref_on_list_position(this, select_lex, i,
(char *) "<no matter>",
(char *) "<list ref>");
func=
Item_bool_func2::eq_creator(new Item_ref((*optimizer->get_cache())->
addr(i),
(char *)"<no matter>",
(char *)"<left expr>"),
func);
item= and_items(item, func);
}
if (join->having || select_lex->with_sum_func ||
select_lex->group_list.first ||
!select_lex->table_list.elements)
{
join->having= and_items(join->having, item);
select_lex->having_fix_field= 1;
if (join->having->fix_fields(thd, join->tables_list, &join->having))
{
Item *func=
new Item_ref_on_list_position(this, sl, i,
(char *) "<no matter>",
(char *) "<list ref>");
func=
Item_bool_func2::eq_creator(new Item_ref((*optimizer->get_cache())->
addr(i),
(char *)"<no matter>",
(char *)"<left expr>"),
func);
item= and_items(item, func);
select_lex->having_fix_field= 0;
DBUG_RETURN(ERROR);
}
if (sl->having || sl->with_sum_func || sl->group_list.first ||
!sl->table_list.elements)
sl->having= and_items(sl->having, item);
else
sl->where= and_items(sl->where, item);
select_lex->having_fix_field= 0;
}
DBUG_VOID_RETURN;
else
{
join->conds= and_items(join->conds, item);
if (join->conds->fix_fields(thd, join->tables_list, &join->having))
DBUG_RETURN(ERROR);
}
DBUG_RETURN(OK);
}
void Item_in_subselect::select_transformer(THD *thd, st_select_lex_unit *unit)
Item_subselect::trans_res
Item_in_subselect::select_transformer(THD *thd, JOIN *join)
{
if (left_expr->cols() == 1)
single_value_transformer(thd, unit, left_expr,
&Item_bool_func2::eq_creator);
return single_value_transformer(thd, join, left_expr,
&Item_bool_func2::eq_creator);
else
row_value_transformer(thd, unit, left_expr);
return row_value_transformer(thd, join, left_expr);
}
void Item_allany_subselect::select_transformer(THD *thd,
st_select_lex_unit *unit)
Item_subselect::trans_res
Item_allany_subselect::select_transformer(THD *thd,
JOIN *join)
{
single_value_transformer(thd, unit, left_expr, func);
return single_value_transformer(thd, join, left_expr, func);
}
subselect_single_select_engine::subselect_single_select_engine(THD *thd,
......
sql/item_subselect.h
View file @ a32b868c
......@@ -46,6 +46,8 @@ protected:
bool have_to_be_excluded;
public:
enum trans_res {OK, REDUCE, ERROR};
Item_subselect();
Item_subselect(Item_subselect *item)
{
......@@ -71,7 +73,7 @@ public:
{
null_value= 1;
}
virtual void select_transformer(THD *thd, st_select_lex_unit *unit);
virtual trans_res select_transformer(THD *thd, JOIN *join);
bool assigned() { return value_assigned; }
void assigned(bool a) { value_assigned= a; }
enum Type type() const;
......@@ -83,6 +85,13 @@ public:
bool fix_fields(THD *thd, TABLE_LIST *tables, Item **ref);
virtual void fix_length_and_dec();
table_map used_tables() const;
void print(String *str)
{
if (name)
str->append(name);
else
str->append("-subselect-");
}
friend class select_subselect;
friend class Item_in_optimizer;
......@@ -105,7 +114,7 @@ public:
decimals= item->decimals;
}
void reset();
void select_transformer(THD *thd, st_select_lex_unit *unit);
trans_res select_transformer(THD *thd, JOIN *join);
void store(uint i, Item* item);
double val();
longlong val_int ();
......@@ -161,25 +170,35 @@ class Item_in_subselect :public Item_exists_subselect
{
protected:
Item * left_expr;
/*
expr & optinizer used in subselect rewriting to store Item for
all JOIN in UNION
*/
Item *expr;
Item_in_optimizer *optimizer;
bool was_null;
bool abort_on_null;
public:
Item_in_subselect(THD *thd, Item * left_expr, st_select_lex *select_lex);
Item_in_subselect(Item_in_subselect *item);
Item_in_subselect(): Item_exists_subselect() {}
Item_in_subselect(): Item_exists_subselect(), abort_on_null(0) {}
void reset()
{
value= 0;
null_value= 0;
was_null= 0;
}
virtual void select_transformer(THD *thd, st_select_lex_unit *unit);
void single_value_transformer(THD *thd, st_select_lex_unit *unit,
Item *left_expr, compare_func_creator func);
void row_value_transformer(THD *thd, st_select_lex_unit *unit,
Item *left_expr);
trans_res select_transformer(THD *thd, JOIN *join);
trans_res single_value_transformer(THD *thd, JOIN *join,
Item *left_expr,
compare_func_creator func);
trans_res row_value_transformer(THD *thd, JOIN * join,
Item *left_expr);
longlong val_int();
double val();
String *val_str(String*);
void top_level_item() { abort_on_null=1; }
bool test_limit(st_select_lex_unit *unit);
friend class Item_asterisk_remover;
friend class Item_ref_null_helper;
......@@ -196,7 +215,7 @@ public:
Item_allany_subselect(THD *thd, Item * left_expr, compare_func_creator f,
st_select_lex *select_lex);
Item_allany_subselect(Item_allany_subselect *item);
virtual void select_transformer(THD *thd, st_select_lex_unit *unit);
trans_res select_transformer(THD *thd, JOIN *join);
};
class subselect_engine: public Sql_alloc
......
sql/sql_derived.cc
View file @ a32b868c
......@@ -196,7 +196,8 @@ int mysql_derived(THD *thd, LEX *lex, SELECT_LEX_UNIT *unit,
if (tables)
{
for (TABLE_LIST *cursor= tables; cursor; cursor= cursor->next)
cursor->table_list->table=cursor->table;
if (cursor->table_list)
cursor->table_list->table=cursor->table;
}
}
else
......
sql/sql_lex.cc
View file @ a32b868c
......@@ -1302,11 +1302,13 @@ bool st_select_lex_unit::create_total_list_n_last_return(THD *thd, st_lex *lex,
return 1;
}
*new_table_list= cursor;
cursor->table_list= aux; //to be able mark this table as shared
new_table_list= &cursor->next;
*new_table_list= 0; // end result list
}
else
aux->shared= 1; // Mark that it's used twice
// Mark that it's used twice
cursor->table_list->shared= aux->shared= 1;
aux->table_list= cursor;
}
}
......@@ -1403,6 +1405,7 @@ ulong st_select_lex::get_table_join_options()
}
st_select_lex::st_select_lex(struct st_lex *lex)
:fake_select(0)
{
select_number= ++lex->thd->select_number;
init_query();
......
sql/sql_lex.h
View file @ a32b868c
......@@ -352,6 +352,8 @@ public:
bool braces; /* SELECT ... UNION (SELECT ... ) <- this braces */
/* TRUE when having fix field called in processing of this SELECT */
bool having_fix_field;
/* TRUE for fake select, which used in UNION processing */
bool fake_select;
void init_query();
void init_select();
......@@ -405,7 +407,7 @@ public:
friend void mysql_init_query(THD *thd);
st_select_lex(struct st_lex *lex);
st_select_lex() {}
st_select_lex() :fake_select(0) {}
void make_empty_select(st_select_lex *last_select)
{
select_number=INT_MAX;
......
sql/sql_olap.cc
View file @ a32b868c
......@@ -150,7 +150,8 @@ int handle_olaps(LEX *lex, SELECT_LEX *select_lex)
{
if (cursor->do_redirect)
{
cursor->table= ((TABLE_LIST*) cursor->table)->table;
//Sinisa TODO: there are function for this purpose: fix_tables_pointers
cursor->table= cursor->table_list->table;
cursor->do_redirect= 0;
}
}
......
sql/sql_select.cc
View file @ a32b868c
......@@ -201,7 +201,8 @@ void relink_tables(SELECT_LEX *select_lex)
for (TABLE_LIST *cursor= (TABLE_LIST *) select_lex->table_list.first;
cursor;
cursor=cursor->next)
cursor->table= cursor->table_list->table;
if (cursor->table_list)
cursor->table= cursor->table_list->table;
}
......@@ -314,6 +315,19 @@ JOIN::prepare(Item ***rref_pointer_array,
having->split_sum_func(ref_pointer_array, all_fields);
}
// Is it subselect
{
Item_subselect *subselect;
if ((subselect= select_lex->master_unit()->item) &&
!select_lex->fake_select)
{
Item_subselect::trans_res res;
if ((res= subselect->select_transformer(thd, this)) !=
Item_subselect::OK)
DBUG_RETURN((res == Item_subselect::ERROR));
}
}
if (setup_ftfuncs(select_lex)) /* should be after having->fix_fields */
DBUG_RETURN(-1);
/*
......
sql/sql_union.cc
View file @ a32b868c
......@@ -188,42 +188,33 @@ int st_select_lex_unit::prepare(THD *thd, select_result *sel_result,
union_result->not_describe=1;
union_result->tmp_table_param=tmp_table_param;
/*
The following piece of code is placed here solely for the purpose of
getting correct results with EXPLAIN when UNION is withing a sub-select
or derived table ...
*/
if (thd->lex.describe)
for (SELECT_LEX *sl= select_cursor; sl; sl= sl->next_select())
{
for (SELECT_LEX *sl= select_cursor; sl; sl= sl->next_select())
{
JOIN *join= new JOIN(thd, sl->item_list,
sl->options | thd->options | SELECT_NO_UNLOCK,
union_result);
thd->lex.current_select= sl;
offset_limit_cnt= sl->offset_limit;
select_limit_cnt= sl->select_limit+sl->offset_limit;
if (select_limit_cnt < sl->select_limit)
select_limit_cnt= HA_POS_ERROR; // no limit
if (select_limit_cnt == HA_POS_ERROR)
sl->options&= ~OPTION_FOUND_ROWS;
res= join->prepare(&sl->ref_pointer_array,
(TABLE_LIST*) sl->table_list.first, sl->with_wild,
sl->where,
((sl->braces) ? sl->order_list.elements : 0) +
sl->group_list.elements,
(sl->braces) ?
(ORDER *)sl->order_list.first : (ORDER *) 0,
(ORDER*) sl->group_list.first,
sl->having,
(ORDER*) NULL,
sl, this, t_and_f);
t_and_f= 0;
if (res || thd->is_fatal_error)
goto err;
}
JOIN *join= new JOIN(thd, sl->item_list,
sl->options | thd->options | SELECT_NO_UNLOCK,
union_result);
thd->lex.current_select= sl;
offset_limit_cnt= sl->offset_limit;
select_limit_cnt= sl->select_limit+sl->offset_limit;
if (select_limit_cnt < sl->select_limit)
select_limit_cnt= HA_POS_ERROR; // no limit
if (select_limit_cnt == HA_POS_ERROR)
sl->options&= ~OPTION_FOUND_ROWS;
res= join->prepare(&sl->ref_pointer_array,
(TABLE_LIST*) sl->table_list.first, sl->with_wild,
sl->where,
((sl->braces) ? sl->order_list.elements : 0) +
sl->group_list.elements,
(sl->braces) ?
(ORDER *)sl->order_list.first : (ORDER *) 0,
(ORDER*) sl->group_list.first,
sl->having,
(ORDER*) NULL,
sl, this, t_and_f);
t_and_f= 0;
if (res || thd->is_fatal_error)
goto err;
}
item_list.empty();
......@@ -268,14 +259,12 @@ int st_select_lex_unit::exec()
}
for (SELECT_LEX *sl= select_cursor; sl; sl= sl->next_select())
{
thd->lex.current_select= sl;
if (optimized)
res= sl->join->reinit();
else
{
JOIN *join= new JOIN(thd, sl->item_list,
sl->options | thd->options | SELECT_NO_UNLOCK,
union_result);
thd->lex.current_select= sl;
offset_limit_cnt= sl->offset_limit;
select_limit_cnt= sl->select_limit+sl->offset_limit;
if (select_limit_cnt < sl->select_limit)
......@@ -283,22 +272,36 @@ int st_select_lex_unit::exec()
if (select_limit_cnt == HA_POS_ERROR)
sl->options&= ~OPTION_FOUND_ROWS;
res= join->prepare(&sl->ref_pointer_array,
(TABLE_LIST*) sl->table_list.first, sl->with_wild,
sl->where,
((sl->braces) ? sl->order_list.elements : 0) +
sl->group_list.elements,
(sl->braces) ?
(ORDER *)sl->order_list.first : (ORDER *) 0,
(ORDER*) sl->group_list.first,
sl->having,
(ORDER*) NULL,
sl, this, t_and_f);
t_and_f=0;
if (res | thd->is_fatal_error)
/*
As far as union share table space we should reassign table map,
which can be spoiled by 'prepare' of JOIN of other UNION parts
if it use same tables
*/
uint tablenr=0;
for (TABLE_LIST *table_list= (TABLE_LIST*) sl->table_list.first;
table_list;
table_list= table_list->next, tablenr++)
{
thd->lex.current_select= lex_select_save;
DBUG_RETURN(res);
if (table_list->shared)
{
/*
review notes: Check it carefully. I still can't understand
why I should not touch table->used_keys. For my point of
view we should do here same procedura as it was done by
setup_table
*/
DBUG_PRINT("SUBS", ("shared %s", table_list->real_name));
TABLE *table= table_list->table;
table->used_fields=0;
table->const_table=0;
table->outer_join=table->null_row=0;
table->status=STATUS_NO_RECORD;
table->keys_in_use_for_query= table->keys_in_use;
table->maybe_null=test(table->outer_join=table_list->outer_join);
table->tablenr=tablenr;
table->map= (table_map) 1 << tablenr;
table->force_index= table_list->force_index;
}
}
res= sl->join->optimize();
}
......@@ -334,6 +337,7 @@ int st_select_lex_unit::exec()
if (!thd->is_fatal_error) // Check if EOM
{
SELECT_LEX *fake_select = new SELECT_LEX(&thd->lex);
fake_select->fake_select= 1;
offset_limit_cnt= (select_cursor->braces ?
global_parameters->offset_limit : 0);
select_limit_cnt= (select_cursor->braces ?
......
sql/sql_yacc.yy
View file @ a32b868c
......@@ -5003,7 +5003,9 @@ subselect_start:
{
LEX *lex=Lex;
if (((int)lex->sql_command >= (int)SQLCOM_HA_OPEN &&
lex->sql_command <= (int)SQLCOM_HA_READ) || lex->sql_command == (int)SQLCOM_KILL) {
lex->sql_command <= (int)SQLCOM_HA_READ) ||
lex->sql_command == (int)SQLCOM_KILL)
{
send_error(lex->thd, ER_SYNTAX_ERROR);
YYABORT;
}
......
sql/table.h
View file @ a32b868c
......@@ -163,15 +163,8 @@ typedef struct st_table_list
struct st_table_list *natural_join; /* natural join on this table*/
/* ... join ... USE INDEX ... IGNORE INDEX */
List<String> *use_index, *ignore_index;
/*
Usually hold reference on opened table, but may hold reference
to node of complete list of tables used in UNION & subselect.
*/
union
{
TABLE *table; /* opened table */
st_table_list *table_list; /* pointer to node of list of all tables */
};
TABLE *table; /* opened table */
st_table_list *table_list; /* pointer to node of list of all tables */
class st_select_lex_unit *derived; /* SELECT_LEX_UNIT of derived table */
GRANT_INFO grant;
thr_lock_type lock_type;
......
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