Skip to content

M
mariadb
Commit 71f6ab7a authored by igor@rurik.mysql.com's avatar igor@rurik.mysql.com
Browse files
Options

Merge for Item_equal.

parents 80d2d8d6 0dcc255b
Expand all Hide whitespace changes
Inline Side-by-side
Showing with 1658 additions and 138 deletions
.bzrignore
View file @ 71f6ab7a
......@@ -508,6 +508,7 @@ mysql-test/install_test_db
mysql-test/mysql-test-run
mysql-test/ndb/ndbcluster
mysql-test/r/*.reject
mysql-test/r/index_merge_load.result
mysql-test/r/rpl000001.eval
mysql-test/r/rpl000002.eval
mysql-test/r/rpl000014.eval
......@@ -518,6 +519,7 @@ mysql-test/r/slave-running.eval
mysql-test/r/slave-stopped.eval
mysql-test/share/mysql
mysql-test/std_data/*.pem
mysql-test/t/index_merge.load
mysql-test/var/*
mysql.kdevprj
mysql.proj
......
mysql-test/r/func_group.result
View file @ 71f6ab7a
......@@ -476,7 +476,7 @@ CHI Los Angeles
explain
select max(a3) from t1 where a2 is null and a2 = 2;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Impossible WHERE noticed after reading const tables
1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Impossible WHERE
select max(a3) from t1 where a2 is null and a2 = 2;
max(a3)
NULL
......
mysql-test/r/func_test.result
View file @ 71f6ab7a
......@@ -77,7 +77,7 @@ select * from t1 where 1 xor 1;
a
explain extended select * from t1 where 1 xor 1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Impossible WHERE noticed after reading const tables
1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Impossible WHERE
Warnings:
Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` where (1 xor 1)
select - a from t1;
......
mysql-test/r/index_merge.result
View file @ 71f6ab7a
......@@ -76,13 +76,13 @@ id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t0 ALL i1,i2 NULL NULL NULL 1024 Using where
explain select * from t0 where key2 = 45 or key1 is null;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t0 range i1,i2 i2 4 NULL 1 Using where
1 SIMPLE t0 ref i2 i2 4 const 1
explain select * from t0 where key2=10 or key3=3 or key4 <=> null;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t0 index_merge i2,i3,i4 i2,i3 4,4 NULL 2 Using union(i2,i3); Using where
explain select * from t0 where key2=10 or key3=3 or key4 is null;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t0 index_merge i2,i3,i4 i2,i3 4,4 NULL 2 Using union(i2,i3); Using where
1 SIMPLE t0 index_merge i2,i3 i2,i3 4,4 NULL 2 Using where
explain select key1 from t0 where (key1 <=> null) or (key2 < 5) or
(key3=10) or (key4 <=> null);
id select_type table type possible_keys key key_len ref rows Extra
......
mysql-test/r/odbc.result
View file @ 71f6ab7a
......@@ -12,5 +12,5 @@ select * from t1 where a is null;
a b
explain select * from t1 where b is null;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Impossible WHERE noticed after reading const tables
1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Impossible WHERE
drop table t1;
mysql-test/r/range.result
View file @ 71f6ab7a
......@@ -220,24 +220,22 @@ insert into t1 (x) values (1),(2),(3),(4),(5),(6),(7),(8),(9);
update t1 set y=x;
explain select * from t1, t1 t2 where t1.y = 2 and t2.x between 7 and t1.y+0;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref y y 5 const 1 Using where
1 SIMPLE t2 range x x 5 NULL 4 Using where
1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Impossible WHERE noticed after reading const tables
explain select * from t1, t1 t2 where t1.y = 2 and t2.x >= 7 and t2.x <= t1.y+0;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref y y 5 const 1 Using where
1 SIMPLE t2 range x x 5 NULL 4 Using where
1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Impossible WHERE noticed after reading const tables
explain select * from t1, t1 t2 where t1.y = 2 and t2.x between t1.y-1 and t1.y+1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref y y 5 const 1 Using where
1 SIMPLE t2 ALL x NULL NULL NULL 9 Range checked for each record (index map: 0x1)
1 SIMPLE t2 range x x 5 NULL 3 Using where
explain select * from t1, t1 t2 where t1.y = 2 and t2.x >= t1.y-1 and t2.x <= t1.y+1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref y y 5 const 1 Using where
1 SIMPLE t2 ALL x NULL NULL NULL 9 Range checked for each record (index map: 0x1)
1 SIMPLE t2 range x x 5 NULL 3 Using where
explain select * from t1, t1 t2 where t1.y = 2 and t2.x between 0 and t1.y;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref y y 5 const 1 Using where
1 SIMPLE t2 ALL x NULL NULL NULL 9 Using where
1 SIMPLE t2 range x x 5 NULL 2 Using where
explain select * from t1, t1 t2 where t1.y = 2 and t2.x >= 0 and t2.x <= t1.y;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref y y 5 const 1 Using where
......@@ -415,14 +413,26 @@ count(*)
select count(*) from t2;
count(*)
1026
analyze table t1,t2;
Table Op Msg_type Msg_text
test.t1 analyze status OK
test.t2 analyze status Table is already up to date
explain select * from t1, t2 where t1.uid=t2.uid AND t1.uid > 0;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range uid_index uid_index 4 NULL 128 Using where
1 SIMPLE t2 ref uid_index uid_index 4 test.t1.uid 38
explain select * from t1, t2 where t1.uid=t2.uid AND t2.uid > 0;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range uid_index uid_index 4 NULL 128 Using where
1 SIMPLE t2 ref uid_index uid_index 4 test.t1.uid 38
explain select * from t1, t2 where t1.uid=t2.uid AND t1.uid != 0;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range uid_index uid_index 4 NULL 129 Using where
1 SIMPLE t2 ref uid_index uid_index 4 test.t1.uid 38
explain select * from t1, t2 where t1.uid=t2.uid AND t2.uid != 0;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range uid_index uid_index 4 NULL 129 Using where
1 SIMPLE t2 ref uid_index uid_index 4 test.t1.uid 38
select * from t1, t2 where t1.uid=t2.uid AND t1.uid > 0;
id name uid id name uid
1001 A 1 1001 A 1
......
mysql-test/r/select.result
View file @ 71f6ab7a
......@@ -1375,7 +1375,7 @@ id select_type table type possible_keys key key_len ref rows Extra
explain select t2.companynr,companyname from t4 left join t2 using (companynr) where t2.companynr > 0 and t4.companynr > 0;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t2 ALL NULL NULL NULL NULL 1199 Using where
1 SIMPLE t4 eq_ref PRIMARY PRIMARY 1 test.t2.companynr 1 Using where
1 SIMPLE t4 eq_ref PRIMARY PRIMARY 1 test.t2.companynr 1
explain select t2.companynr,companyname from t4 left join t2 using (companynr) where t2.companynr > 0 or t2.companynr is null;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t4 ALL NULL NULL NULL NULL 12
......
mysql-test/t/range.test
View file @ 71f6ab7a
......@@ -378,8 +378,12 @@ insert into t2(id, uid, name) select id, uid, name from t1;
select count(*) from t1;
select count(*) from t2;
analyze table t1,t2;
explain select * from t1, t2 where t1.uid=t2.uid AND t1.uid > 0;
explain select * from t1, t2 where t1.uid=t2.uid AND t2.uid > 0;
explain select * from t1, t2 where t1.uid=t2.uid AND t1.uid != 0;
explain select * from t1, t2 where t1.uid=t2.uid AND t2.uid != 0;
select * from t1, t2 where t1.uid=t2.uid AND t1.uid > 0;
select * from t1, t2 where t1.uid=t2.uid AND t1.uid != 0;
......
sql/item.cc
View file @ 71f6ab7a
......@@ -408,6 +408,7 @@ bool DTCollation::aggregate(DTCollation &dt, bool superset_conversion)
Item_field::Item_field(Field *f)
:Item_ident(NullS, f->table_name, f->field_name),
item_equal(0),
have_privileges(0), any_privileges(0)
{
set_field(f);
......@@ -418,6 +419,7 @@ Item_field::Item_field(Field *f)
Item_field::Item_field(THD *thd, Field *f)
:Item_ident(NullS, thd->strdup(f->table_name),
thd->strdup(f->field_name)),
item_equal(0),
have_privileges(0), any_privileges(0)
{
set_field(f);
......@@ -434,6 +436,7 @@ Item_field::Item_field(THD *thd, Item_field *item)
any_privileges(item->any_privileges)
{
collation.set(DERIVATION_IMPLICIT);
item_equal= item->item_equal;
}
void Item_field::set_field(Field *field_par)
......@@ -1582,7 +1585,29 @@ void Item_field::cleanup()
I.e. we can drop 'field'.
*/
field= result_field= 0;
DBUG_VOID_RETURN;
}
/*
Find a field among specified multiple equalities
SYNOPSIS
find_item_equal()
cond_equal reference to list of multiple equalities where
the field (this object) is to be looked for
DESCRIPTION
The function first searches the field among multiple equalities
of the current level (in the cond_equal->current_level list).
If it fails, it continues searching in upper levels accessed
through a pointer cond_equal->upper_levels.
The search terminates as soon as a multiple equality containing
the field is found.
RETURN VALUES
First Item_equal containing the field, if success
0, otherwise
*/
}
void Item::init_make_field(Send_field *tmp_field,
......
sql/item.h
View file @ 71f6ab7a
......@@ -90,6 +90,7 @@ public:
};
typedef bool (Item::*Item_processor)(byte *arg);
typedef Item* (Item::*Item_transformer) (byte *arg);
class Item {
Item(const Item &); /* Prevent use of these */
......@@ -261,8 +262,15 @@ public:
return (this->*processor)(arg);
}
virtual Item* transform(Item_transformer transformer, byte *arg)
{
return (this->*transformer)(arg);
}
virtual bool remove_dependence_processor(byte * arg) { return 0; }
virtual bool remove_fixed(byte * arg) { fixed= 0; return 0; }
virtual Item *equal_fields_propagator(byte * arg) { return this; }
virtual bool replace_equal_field_processor(byte * arg) { return 0; }
virtual Item *this_item() { return this; } /* For SPs mostly. */
virtual Item *this_const_item() const { return const_cast<Item*>(this); } /* For SPs mostly. */
......@@ -440,6 +448,8 @@ public:
bool any_privileges, bool allocate_view_names);
};
class Item_equal;
class COND_EQUAL;
class Item_field :public Item_ident
{
......@@ -458,7 +468,8 @@ public:
Item_field(const char *db_par,const char *table_name_par,
const char *field_name_par)
:Item_ident(db_par,table_name_par,field_name_par),
field(0), result_field(0), have_privileges(0), any_privileges(0)
field(0), result_field(0), item_equal(0),}
have_privileges(0), any_privileges(0)
{ collation.set(DERIVATION_IMPLICIT); }
// Constructor need to process subselect with temporary tables (see Item)
Item_field(THD *thd, Item_field *item);
......@@ -498,6 +509,9 @@ public:
bool is_null() { return field->is_null(); }
Item *get_tmp_table_item(THD *thd);
void cleanup();
Item_equal *find_item_equal(COND_EQUAL *cond_equal);
Item *equal_fields_propagator(byte *arg);
bool replace_equal_field_processor(byte *arg);
inline uint32 max_disp_length() { return field->max_length(); }
Item_field *filed_for_view_update() { return this; }
friend class Item_default_value;
......@@ -1173,6 +1187,19 @@ public:
return arg->walk(processor, args) ||
(this->*processor)(args);
}
/*
This method like the walk method traverses the item tree, but
at the same time it can replace some nodes in the tree
*/
Item *transform(Item_transformer transformer, byte *args)
{
Item *new_item= arg->transform(transformer, args);
if (!new_item)
return 0;
arg= new_item;
return (this->*transformer)(args);
}
};
class Item_insert_value : public Item_field
......
sql/item_cmpfunc.cc
View file @ 71f6ab7a
......@@ -256,7 +256,7 @@ void Item_bool_func2::fix_length_and_dec()
}
}
}
if (args[1]->type() == FIELD_ITEM)
if (args[1]->type() == FIELD_ITEM /* && !args[1]->const_item() */)
{
Field *field=((Item_field*) args[1])->field;
if (field->store_for_compare())
......@@ -2008,6 +2008,44 @@ bool Item_cond::walk(Item_processor processor, byte *arg)
return Item_func::walk(processor, arg);
}
/*
Transform an Item_cond object with a transformer callback function
SYNOPSIS
transform()
transformer the transformer callback function to be applied to the nodes
of the tree of the object
arg parameter to be passed to the transformer
DESCRIPTION
The function recursively applies the transform method with the
same transformer to each member item of the codition list.
If the call of the method for a member item returns a new item
the old item is substituted for a new one.
After this the transform method is applied to the root node
of the Item_cond object.
RETURN VALUES
Item returned as the result of transformation of the root node
*/
Item *Item_cond::transform(Item_transformer transformer, byte *arg)
{
List_iterator<Item> li(list);
Item *item;
while ((item= li++))
{
Item *new_item= item->transform(transformer, arg);
if (!new_item)
return 0;
if (new_item != item)
li.replace(new_item);
}
return Item_func::transform(transformer, arg);
}
void Item_cond::split_sum_func(Item **ref_pointer_array, List<Item> &fields)
{
List_iterator<Item> li(list);
......@@ -2854,3 +2892,289 @@ Item *Item_bool_rowready_func2::negated_item()
DBUG_ASSERT(0);
return 0;
}
Item_equal::Item_equal(Item_field *f1, Item_field *f2)
: Item_bool_func(), const_item(0), eval_item(0), cond_false(0)
{
const_item_cache= 0;
fields.push_back(f1);
fields.push_back(f2);
}
Item_equal::Item_equal(Item *c, Item_field *f)
: Item_bool_func(), eval_item(0), cond_false(0)
{
const_item_cache= 0;
fields.push_back(f);
const_item= c;
}
Item_equal::Item_equal(Item_equal *item_equal)
: Item_bool_func(), eval_item(0), cond_false(0)
{
const_item_cache= 0;
List_iterator_fast<Item_field> li(item_equal->fields);
Item_field *item;
while ((item= li++))
{
fields.push_back(item);
}
const_item= item_equal->const_item;
cond_false= item_equal->cond_false;
}
void Item_equal::add(Item *c)
{
if (cond_false)
return;
if (!const_item)
{
const_item= c;
return;
}
Item_func_eq *func= new Item_func_eq(c, const_item);
func->set_cmp_func();
cond_false = !(func->val_int());
}
void Item_equal::add(Item_field *f)
{
fields.push_back(f);
}
uint Item_equal::members()
{
uint count= 0;
List_iterator_fast<Item_field> li(fields);
Item_field *item;
while ((item= li++))
count++;
return count;
}
/*
Check whether a field is referred in the multiple equality
SYNOPSIS
contains()
field field whose occurence is to be checked
DESCRIPTION
The function checks whether field is occured in the Item_equal object
RETURN VALUES
1 if nultiple equality contains a reference to field
0 otherwise
*/
bool Item_equal::contains(Field *field)
{
List_iterator_fast<Item_field> it(fields);
Item_field *item;
while ((item= it++))
{
if (field->eq(item->field))
return 1;
}
return 0;
}
/*
Join members of another Item_equal object
SYNOPSIS
merge()
item multiple equality whose members are to be joined
DESCRIPTION
The function actually merges two multiple equalitis.
After this operation the Item_equal object additionally contains
the field items of another item of the type Item_equal.
If the optional constant items are not equal the cond_false flag is
set to 1.
RETURN VALUES
none
*/
void Item_equal::merge(Item_equal *item)
{
fields.concat(&item->fields);
Item *c= item->const_item;
if (c)
{
/*
The flag cond_false will be set to 1 after this, if
the multiple equality already contains a constant and its
value is not equal to the value of c.
*/
add(const_item);
}
cond_false|= item->cond_false;
}
/*
Order field items in multiple equality according to a sorting criteria
SYNOPSIS
sort()
cmp function to compare field item
arg context extra parameter for the cmp function
DESCRIPTION
The function perform ordering of the field items in the Item_equal
object according to the criteria determined by the cmp callback parameter.
If cmp(item_field1,item_field2,arg)<0 than item_field1 must be
placed after item_fiel2.
IMPLEMENTATION
The function sorts field items by the exchange sort algorithm.
The list of field items is looked through and whenever two neighboring
members follow in a wrong order they are swapped. This is performed
again and again until we get all members in a right order.
RETURN VALUES
None
*/
void Item_equal::sort(Item_field_cmpfunc cmp, void *arg)
{
bool swap;
List_iterator<Item_field> it(fields);
do
{
Item_field *item1= it++;
Item_field **ref1= it.ref();
Item_field *item2;
swap= FALSE;
while ((item2= it++))
{
Item_field **ref2= it.ref();
if (cmp(item1, item2, arg) < 0)
{
Item_field *item= *ref1;
*ref1= *ref2;
*ref2= item;
swap= TRUE;
}
else
{
item1= item2;
ref1= ref2;
}
}
it.rewind();
} while (swap);
}
bool Item_equal::fix_fields(THD *thd, TABLE_LIST *tables, Item **ref)
{
List_iterator_fast<Item_field> li(fields);
Item *item;
not_null_tables_cache= used_tables_cache= 0;
const_item_cache= 0;
while ((item=li++))
{
table_map tmp_table_map;
used_tables_cache|= item->used_tables();
tmp_table_map= item->not_null_tables();
not_null_tables_cache|= tmp_table_map;
if (item->maybe_null)
maybe_null=1;
}
fix_length_and_dec();
fixed= 1;
return 0;
}
void Item_equal::update_used_tables()
{
List_iterator_fast<Item_field> li(fields);
Item *item;
not_null_tables_cache= used_tables_cache= 0;
if ((const_item_cache= cond_false))
return;
while ((item=li++))
{
item->update_used_tables();
used_tables_cache|= item->used_tables();
const_item_cache&= item->const_item();
}
}
longlong Item_equal::val_int()
{
if (cond_false)
return 0;
List_iterator_fast<Item_field> it(fields);
Item *item= const_item ? const_item : it++;
if ((null_value= item->null_value))
return 0;
eval_item->store_value(item);
while ((item= it++))
{
if ((null_value= item->null_value) || eval_item->cmp(item))
return 0;
}
return 1;
}
void Item_equal::fix_length_and_dec()
{
Item *item= const_item ? const_item : get_first();
eval_item= cmp_item::get_comparator(item);
if (item->result_type() == STRING_RESULT)
eval_item->cmp_charset= cmp_collation.collation;
}
bool Item_equal::walk(Item_processor processor, byte *arg)
{
List_iterator_fast<Item_field> it(fields);
Item *item;
while ((item= it++))
if (item->walk(processor, arg))
return 1;
return Item_func::walk(processor, arg);
}
Item *Item_equal::transform(Item_transformer transformer, byte *arg)
{
List_iterator<Item_field> it(fields);
Item *item;
while ((item= it++))
{
Item *new_item= item->transform(transformer, arg);
if (!new_item)
return 0;
if (new_item != item)
it.replace((Item_field *) new_item);
}
return Item_func::transform(transformer, arg);
}
void Item_equal::print(String *str)
{
str->append(func_name());
str->append('(');
List_iterator_fast<Item_field> it(fields);
Item *item;
if (const_item)
const_item->print(str);
else
{
item= it++;
item->print(str);
}
while ((item= it++))
{
str->append(',');
str->append(' ');
item->print(str);
}
str->append(')');
}
sql/item_cmpfunc.h
View file @ 71f6ab7a
......@@ -20,6 +20,9 @@
#ifdef __GNUC__
#pragma interface /* gcc class implementation */
#endif
#ifdef __GNUC__
template class List_iterator_fast<Item_field>;
#endif
extern Item_result item_cmp_type(Item_result a,Item_result b);
class Item_bool_func2;
......@@ -27,6 +30,8 @@ class Arg_comparator;
typedef int (Arg_comparator::*arg_cmp_func)();
typedef int (*Item_field_cmpfunc)(Item_field *f1, Item_field *f2, void *arg);
class Arg_comparator: public Sql_alloc
{
Item **a, **b;
......@@ -957,6 +962,7 @@ public:
Item_cond(List<Item> &nlist)
:Item_bool_func(), list(nlist), abort_on_null(0) {}
bool add(Item *item) { return list.push_back(item); }
void add_at_head(List<Item> *nlist) { list.prepand(nlist); }
bool fix_fields(THD *, struct st_table_list *, Item **ref);
enum Type type() const { return COND_ITEM; }
......@@ -969,13 +975,151 @@ public:
void top_level_item() { abort_on_null=1; }
void copy_andor_arguments(THD *thd, Item_cond *item);
bool walk(Item_processor processor, byte *arg);
Item *transform(Item_transformer transformer, byte *arg);
void neg_arguments(THD *thd);
};
/*
The class Item_equal is used to represent conjuctions of equality
predicates of the form field1 = field2, and field=const in where
conditions and on expressions.
All equality predicates of the form field1=field2 contained in a
conjuction are substituted for a sequence of items of this class.
An item of this class Item_equal(f1,f2,...fk) respresents a
multiple equality f1=f2=...=fk.
If a conjuction contains predicates f1=f2 and f2=f3, a new item of
this class is created Item_equal(f1,f2,f3) representing the multiple
equality f1=f2=f3 that substitutes the above equality predicates in
the conjuction.
A conjuction of the predicates f2=f1 and f3=f1 and f3=f2 will be
substituted for the item representing the same multiple equality
f1=f2=f3.
An item Item_equal(f1,f2) can appear instead of a conjuction of
f2=f1 and f1=f2, or instead of just the predicate f1=f2.
An item of the class Item_equal inherites equalities from outer
conjunctive levels.
Suppose we have a where condition of the following form:
WHERE f1=f2 AND f3=f4 AND f3=f5 AND ... AND (...OR (f1=f3 AND ...)).
In this case:
f1=f2 will be substituted for Item_equal(f1,f2);
f3=f4 and f3=f5 will be substituted for Item_equal(f3,f4,f5);
f1=f3 will be substituted for Item_equal(f1,f2,f3,f4,f5);
An object of the class Item_equal can contain an optional constant
item c. Thenit represents a multiple equality of the form
c=f1=...=fk.
Objects of the class Item_equal are used for the following:
1. An object Item_equal(t1.f1,...,tk.fk) allows us to consider any
pair of tables ti and tj as joined by an equi-condition.
Thus it provide us with additional access paths from table to table.
2. An object Item_equal(t1.f1,...,tk.fk) is applied to deduce new
SARGable predicates:
f1=...=fk AND P(fi) => f1=...=fk AND P(fi) AND P(fj).
It also can give us additional index scans and can allow us to
improve selectivity estimates.
3. An object Item_equal(t1.f1,...,tk.fk) is used to optimize the
selected execution plan for the query: if table ti is accessed
before the table tj then in any predicate P in the where condition
the occurence of tj.fj is substituted for ti.fi. This can allow
an evaluation of the predicate at an earlier step.
When feature 1 is supported they say that join transitive closure
is employed.
When feature 2 is supported they say that search argument transitive
closure is employed.
Both features are usually supported by preprocessing original query and
adding additional predicates.
We do not just add predicates, we rather dynamically replace some
predicates that can not be used to access tables in the investigated
plan for those, obtained by substitution of some fields for equal fields,
that can be used.
*/
class Item_equal: public Item_bool_func
{
List<Item_field> fields; /* list of equal field items */
Item *const_item; /* optional constant item equal to fields items */
cmp_item *eval_item;
bool cond_false;
DTCollation cmp_collation;
public:
inline Item_equal()
: Item_bool_func(), const_item(0), eval_item(0), cond_false(0)
{ const_item_cache=0 ;}
Item_equal(Item_field *f1, Item_field *f2);
Item_equal(Item *c, Item_field *f);
Item_equal(Item_equal *item_equal);
inline Item* get_const() { return const_item; }
void add(Item *c);
void add(Item_field *f);
uint members();
bool contains(Field *field);
Item_field* get_first() { return fields.head(); }
void merge(Item_equal *item);
enum Functype functype() const { return MULT_EQUAL_FUNC; }
longlong val_int();
const char *func_name() const { return "multiple equal"; }
optimize_type select_optimize() const { return OPTIMIZE_EQUAL; }
void sort(Item_field_cmpfunc cmp, void *arg);
friend class Item_equal_iterator;
void fix_length_and_dec();
bool fix_fields(THD *thd, TABLE_LIST *tables, Item **ref);
void update_used_tables();
bool walk(Item_processor processor, byte *arg);
Item *transform(Item_transformer transformer, byte *arg);
void print(String *str);
CHARSET_INFO *compare_collation()
{ return fields.head()->collation.collation; }
};
class COND_EQUAL
{
public:
uint max_members; /* max number of members the current level
list and all lower level lists */
COND_EQUAL *upper_levels; /* multiple equalities of upper and levels */
List<Item_equal> current_level; /* list of multiple equalities of
the current and level */
COND_EQUAL()
{
max_members= 0;
upper_levels= 0;
}
};
class Item_equal_iterator :List_iterator_fast<Item_field>
{
public:
inline Item_equal_iterator(Item_equal &item_equal)
:List_iterator_fast<Item_field> (item_equal.fields)
{}
inline Item_field* operator++(int)
{
Item_field *item= (*(List_iterator_fast<Item_field> *) this)++;
return item;
}
inline void rewind(void)
{
List_iterator_fast<Item_field>::rewind();
}
};
class Item_cond_and :public Item_cond
{
public:
COND_EQUAL cond_equal; /* contains list of Item_equal objects for
the current and level and reference
to multiple equalities of upper and levels */
Item_cond_and() :Item_cond() {}
Item_cond_and(Item *i1,Item *i2) :Item_cond(i1,i2) {}
Item_cond_and(THD *thd, Item_cond_and *item) :Item_cond(thd, item) {}
......
sql/item_func.cc
View file @ 71f6ab7a
......@@ -260,6 +260,45 @@ bool Item_func::walk (Item_processor processor, byte *argument)
return (this->*processor)(argument);
}
/*
Transform an Item_func object with a transformer callback function
SYNOPSIS
transform()
transformer the transformer callback function to be applied to the nodes
of the tree of the object
argument parameter to be passed to the transformer
DESCRIPTION
The function recursively applies the transform method with the
same transformer to each argument the function.
If the call of the method for a member item returns a new item
the old item is substituted for a new one.
After this the transform method is applied to the root node
of the Item_func object.
RETURN VALUES
Item returned as the result of transformation of the root node
*/
Item *Item_func::transform(Item_transformer transformer, byte *argument)
{
if (arg_count)
{
Item **arg,**arg_end;
for (arg= args, arg_end= args+arg_count; arg != arg_end; arg++)
{
Item *new_item= (*arg)->transform(transformer, argument);
if (!new_item)
return 0;
*arg= new_item;
}
}
return (this->*transformer)(argument);
}
void Item_func::split_sum_func(Item **ref_pointer_array, List<Item> &fields)
{
Item **arg, **arg_end;
......
sql/item_func.h
View file @ 71f6ab7a
......@@ -40,7 +40,8 @@ public:
enum Functype { UNKNOWN_FUNC,EQ_FUNC,EQUAL_FUNC,NE_FUNC,LT_FUNC,LE_FUNC,
GE_FUNC,GT_FUNC,FT_FUNC,
LIKE_FUNC,NOTLIKE_FUNC,ISNULL_FUNC,ISNOTNULL_FUNC,
COND_AND_FUNC, COND_OR_FUNC, COND_XOR_FUNC, BETWEEN, IN_FUNC,
COND_AND_FUNC, COND_OR_FUNC, COND_XOR_FUNC,
BETWEEN, IN_FUNC, MULT_EQUAL_FUNC,
INTERVAL_FUNC, ISNOTNULLTEST_FUNC,
SP_EQUALS_FUNC, SP_DISJOINT_FUNC,SP_INTERSECTS_FUNC,
SP_TOUCHES_FUNC,SP_CROSSES_FUNC,SP_WITHIN_FUNC,
......@@ -50,7 +51,8 @@ public:
NOT_FUNC, NOT_ALL_FUNC,
NOW_FUNC, TRIG_COND_FUNC,
GUSERVAR_FUNC};
enum optimize_type { OPTIMIZE_NONE,OPTIMIZE_KEY,OPTIMIZE_OP, OPTIMIZE_NULL };
enum optimize_type { OPTIMIZE_NONE,OPTIMIZE_KEY,OPTIMIZE_OP, OPTIMIZE_NULL,
OPTIMIZE_EQUAL };
enum Type type() const { return FUNC_ITEM; }
virtual enum Functype functype() const { return UNKNOWN_FUNC; }
Item_func(void):
......@@ -150,6 +152,7 @@ public:
bool allow_superset_comversion= FALSE);
bool walk(Item_processor processor, byte *arg);
Item *transform(Item_transformer transformer, byte *arg);
};
......
sql/item_row.cc
View file @ 71f6ab7a
......@@ -145,6 +145,18 @@ bool Item_row::walk(Item_processor processor, byte *arg)
return (this->*processor)(arg);
}
Item *Item_row::transform(Item_transformer transformer, byte *arg)
{
for (uint i= 0; i < arg_count; i++)
{
Item *new_item= items[i]->transform(transformer, arg);
if (!new_item)
return 0;
items[i]= new_item;
}
return (this->*transformer)(arg);
}
void Item_row::bring_value()
{
for (uint i= 0; i < arg_count; i++)
......
sql/item_row.h
View file @ 71f6ab7a
......@@ -65,6 +65,7 @@ public:
void print(String *str);
bool walk(Item_processor processor, byte *arg);
Item *transform(Item_transformer transformer, byte *arg);
uint cols() { return arg_count; }
Item* el(uint i) { return items[i]; }
......
sql/item_strfunc.h
View file @ 71f6ab7a
......@@ -428,6 +428,14 @@ public:
return item->walk(processor, arg) ||
Item_str_func::walk(processor, arg);
}
Item *transform(Item_transformer transformer, byte *arg)
{
Item *new_item= item->transform(transformer, arg);
if (!new_item)
return 0;
item= new_item;
return Item_str_func::transform(transformer, arg);
}
void print(String *str);
};
......
sql/opt_range.cc
View file @ 71f6ab7a
......@@ -3148,12 +3148,98 @@ QUICK_SELECT_I *TRP_ROR_UNION::make_quick(PARAM *param,
DBUG_RETURN(quick_roru);
}
/****************************************************************************/
/*
Build a SEL_TREE for a simple predicate
SYNOPSIS
get_func_mm_tree()
param PARAM from SQL_SELECT::test_quick_select
cond_func item for the predicate
field field in the predicate
value constant in the predicate
cmp_type compare type for the field
RETURN
Pointer to thre built tree
*/
static SEL_TREE *get_func_mm_tree(PARAM *param, Item_func *cond_func,
Field *field, Item *value,
Item_result cmp_type)
{
SEL_TREE *tree= 0;
DBUG_ENTER("get_func_mm_tree");
switch (cond_func->functype()) {
case Item_func::NE_FUNC:
tree= get_mm_parts(param, cond_func, field, Item_func::LT_FUNC,
value, cmp_type);
if (tree)
{
tree= tree_or(param, tree, get_mm_parts(param, cond_func, field,
Item_func::GT_FUNC,
value, cmp_type));
}
break;
case Item_func::BETWEEN:
tree= get_mm_parts(param, cond_func, field, Item_func::GE_FUNC,
cond_func->arguments()[1],cmp_type);
if (tree)
{
tree= tree_and(param, tree, get_mm_parts(param, cond_func, field,
Item_func::LE_FUNC,
cond_func->arguments()[2],
cmp_type));
}
break;
case Item_func::IN_FUNC:
{
Item_func_in *func=(Item_func_in*) cond_func;
tree= get_mm_parts(param, cond_func, field, Item_func::EQ_FUNC,
func->arguments()[1], cmp_type);
if (tree)
{
Item **arg, **end;
for (arg= func->arguments()+2, end= arg+func->argument_count()-2;
arg < end ; arg++)
{
tree= tree_or(param, tree, get_mm_parts(param, cond_func, field,
Item_func::EQ_FUNC,
*arg,
cmp_type));
}
}
break;
}
default:
{
/*
Here the function for the following predicates are processed:
<, <=, =, >=, >, LIKE, IS NULL, IS NOT NULL.
If the predicate is of the form (value op field) it is handled
as the equivalent predicate (field rev_op value), e.g.
2 <= a is handled as a >= 2.
*/
Item_func::Functype func_type=
(value != cond_func->arguments()[0]) ? cond_func->functype() :
((Item_bool_func2*) cond_func)->rev_functype();
tree= get_mm_parts(param, cond_func, field, func_type, value, cmp_type);
}
}
DBUG_RETURN(tree);
}
/* make a select tree of all keys in condition */
static SEL_TREE *get_mm_tree(PARAM *param,COND *cond)
{
SEL_TREE *tree=0;
SEL_TREE *ftree= 0;
Item_field *field_item= 0;
Item *value;
DBUG_ENTER("get_mm_tree");
if (cond->type() == Item::COND_ITEM)
......@@ -3201,9 +3287,12 @@ static SEL_TREE *get_mm_tree(PARAM *param,COND *cond)
DBUG_RETURN(new SEL_TREE(SEL_TREE::IMPOSSIBLE));
}
table_map ref_tables=cond->used_tables();
table_map ref_tables= 0;
table_map param_comp= ~(param->prev_tables | param->read_tables |
param->current_table);
if (cond->type() != Item::FUNC_ITEM)
{ // Should be a field
ref_tables= cond->used_tables();
if ((ref_tables & param->current_table) ||
(ref_tables & ~(param->prev_tables | param->read_tables)))
DBUG_RETURN(0);
......@@ -3214,80 +3303,42 @@ static SEL_TREE *get_mm_tree(PARAM *param,COND *cond)
if (cond_func->select_optimize() == Item_func::OPTIMIZE_NONE)
DBUG_RETURN(0); // Can't be calculated
param->cond= cond;
if (cond_func->functype() == Item_func::BETWEEN)
switch (cond_func->functype()) {
case Item_func::BETWEEN:
if (cond_func->arguments()[0]->type() != Item::FIELD_ITEM)
DBUG_RETURN(0);
field_item= (Item_field*) (cond_func->arguments()[0]);
value= NULL;
break;
case Item_func::IN_FUNC:
{
if (cond_func->arguments()[0]->type() == Item::FIELD_ITEM)
{
Field *field=((Item_field*) (cond_func->arguments()[0]))->field;
Item_result cmp_type=field->cmp_type();
DBUG_RETURN(tree_and(param,
get_mm_parts(param, cond_func, field,
Item_func::GE_FUNC,
cond_func->arguments()[1], cmp_type),
get_mm_parts(param, cond_func, field,
Item_func::LE_FUNC,
cond_func->arguments()[2], cmp_type)));
}
DBUG_RETURN(0);
}
if (cond_func->functype() == Item_func::IN_FUNC)
{ // COND OR
Item_func_in *func=(Item_func_in*) cond_func;
if (func->key_item()->type() == Item::FIELD_ITEM)
if (func->key_item()->type() != Item::FIELD_ITEM)
DBUG_RETURN(0);
field_item= (Item_field*) (func->key_item());
value= NULL;
break;
}
case Item_func::MULT_EQUAL_FUNC:
{
Item_equal *item_equal= (Item_equal *) cond;
if (!(value= item_equal->get_const()))
DBUG_RETURN(0);
Item_equal_iterator it(*item_equal);
ref_tables= value->used_tables();
while ((field_item= it++))
{
Field *field=((Item_field*) (func->key_item()))->field;
Item_result cmp_type=field->cmp_type();
tree= get_mm_parts(param,cond_func,field,Item_func::EQ_FUNC,
func->arguments()[1],cmp_type);
if (!tree)
DBUG_RETURN(tree); // Not key field
for (uint i=2 ; i < func->argument_count(); i++)
Field *field= field_item->field;
Item_result cmp_type= field->cmp_type();
if (!((ref_tables | field->table->map) & param_comp))
{
SEL_TREE *new_tree=get_mm_parts(param,cond_func,field,
Item_func::EQ_FUNC,
func->arguments()[i],cmp_type);
tree=tree_or(param,tree,new_tree);
tree= get_mm_parts(param, cond, field, Item_func::EQ_FUNC,
value,cmp_type);
ftree= !ftree ? tree : tree_and(param, ftree, tree);
}
DBUG_RETURN(tree);
}
DBUG_RETURN(0); // Can't optimize this IN
}
if (ref_tables & ~(param->prev_tables | param->read_tables |
param->current_table))
DBUG_RETURN(0); // Can't be calculated yet
if (!(ref_tables & param->current_table))
DBUG_RETURN(new SEL_TREE(SEL_TREE::MAYBE)); // This may be FALSE or TRUE
/* check field op const */
/* btw, ft_func's arguments()[0] isn't FIELD_ITEM. SerG*/
if (cond_func->arguments()[0]->type() == Item::FIELD_ITEM)
{
tree= get_mm_parts(param, cond_func,
((Item_field*) (cond_func->arguments()[0]))->field,
cond_func->functype(),
cond_func->arg_count > 1 ? cond_func->arguments()[1] :
0,
((Item_field*) (cond_func->arguments()[0]))->field->
cmp_type());
}
/* check const op field */
if (!tree &&
cond_func->have_rev_func() &&
cond_func->arguments()[1]->type() == Item::FIELD_ITEM)
{
DBUG_RETURN(get_mm_parts(param, cond_func,
((Item_field*)
(cond_func->arguments()[1]))->field,
((Item_bool_func2*) cond_func)->rev_functype(),
cond_func->arguments()[0],
((Item_field*)
(cond_func->arguments()[1]))->field->cmp_type()
));
}
DBUG_RETURN(tree);
DBUG_RETURN(ftree);
}
......@@ -3296,17 +3347,10 @@ get_mm_parts(PARAM *param, COND *cond_func, Field *field,
Item_func::Functype type,
Item *value, Item_result cmp_type)
{
bool ne_func= FALSE;
DBUG_ENTER("get_mm_parts");
if (field->table != param->table)
DBUG_RETURN(0);
if (type == Item_func::NE_FUNC)
{
ne_func= TRUE;
type= Item_func::LT_FUNC;
}
KEY_PART *key_part = param->key_parts;
KEY_PART *end = param->key_parts_end;
SEL_TREE *tree=0;
......@@ -3344,15 +3388,6 @@ get_mm_parts(PARAM *param, COND *cond_func, Field *field,
}
}
if (ne_func)
{
SEL_TREE *tree2= get_mm_parts(param, cond_func,
field, Item_func::GT_FUNC,
value, cmp_type);
if (tree2)
tree= tree_or(param,tree,tree2);
}
DBUG_RETURN(tree);
}
......
sql/opt_sum.cc
View file @ 71f6ab7a
......@@ -341,6 +341,18 @@ static bool simple_pred(Item_func *func_item, Item **args, bool *inv_order)
Item *item;
*inv_order= 0;
switch (func_item->argument_count()) {
case 0:
/* MULT_EQUAL_FUNC */
{
Item_equal *item_equal= (Item_equal *) func_item;
Item_equal_iterator it(*item_equal);
args[0]= it++;
if (it++)
return 0;
if (!(args[1]= item_equal->get_const()))
return 0;
}
break;
case 1:
/* field IS NULL */
item= func_item->arguments()[0];
......@@ -481,6 +493,9 @@ static bool matching_cond(bool max_fl, TABLE_REF *ref, KEY *keyinfo,
case Item_func::BETWEEN:
between= 1;
break;
case Item_func::MULT_EQUAL_FUNC:
eq_type= 1;
break;
default:
return 0; // Can't optimize function
}
......
sql/sql_list.h
View file @ 71f6ab7a
......@@ -127,10 +127,12 @@ public:
void remove(list_node **prev)
{
list_node *node=(*prev)->next;
delete *prev;
*prev=node;
if (!--elements)
last= &first;
else if (last == &(*prev)->next)
last= prev;
delete *prev;
*prev=node;
}
inline void *pop(void)
{
......@@ -143,9 +145,36 @@ public:
}
inline void concat(base_list *list)
{
*last= list->first;
last= list->last;
elements+= list->elements;
if (!list->is_empty())
{
*last= list->first;
last= list->last;
elements+= list->elements;
}
}
inline void disjoin(base_list *list)
{
list_node **prev= &first;
list_node *node= first;
list_node *list_first= list->first;
elements=0;
while (node && node != list_first)
{
prev= &node->next;
node= node->next;
elements++;
}
*prev= *last;
last= prev;
}
inline void prepand(base_list *list)
{
if (!list->is_empty())
{
*list->last= first;
first= list->first;
elements+= list->elements;
}
}
inline list_node* last_node() { return *last; }
inline list_node* first_node() { return first;}
......@@ -257,6 +286,9 @@ public:
inline T* head() {return (T*) base_list::head(); }
inline T** head_ref() {return (T**) base_list::head_ref(); }
inline T* pop() {return (T*) base_list::pop(); }
inline void concat(List<T> *list) { base_list::concat(list); }
inline void disjoin(List<T> *list) { base_list::disjoin(list); }
inline void prepand(List<T> *list) { base_list::prepand(list); }
void delete_elements(void)
{
list_node *element,*next;
......@@ -267,7 +299,6 @@ public:
}
empty();
}
inline void concat(List<T> *list) { base_list::concat(list); }
};
......@@ -278,6 +309,8 @@ public:
inline T* operator++(int) { return (T*) base_list_iterator::next(); }
inline T *replace(T *a) { return (T*) base_list_iterator::replace(a); }
inline T *replace(List<T> &a) { return (T*) base_list_iterator::replace(a); }
inline void rewind(void) { base_list_iterator::rewind(); }
inline void remove() { base_list_iterator::remove(); }
inline void after(T *a) { base_list_iterator::after(a); }
inline T** ref(void) { return (T**) base_list_iterator::ref(); }
};
......
sql/sql_select.cc
View file @ 71f6ab7a
This diff is collapsed.
sql/sql_select.h
View file @ 71f6ab7a
......@@ -222,6 +222,7 @@ class JOIN :public Sql_alloc
Item *conds_history; // store WHERE for explain
TABLE_LIST *tables_list; //hold 'tables' parameter of mysql_select
List<TABLE_LIST> *join_list; // list of joined tables in reverse order
COND_EQUAL *cond_equal;
SQL_SELECT *select; //created in optimisation phase
JOIN_TAB *return_tab; //used only for outer joins
Item **ref_pointer_array; //used pointer reference for this select
......@@ -284,6 +285,7 @@ class JOIN :public Sql_alloc
ref_pointer_array_size= 0;
zero_result_cause= 0;
optimized= 0;
cond_equal= 0;
fields_list= fields_arg;
bzero((char*) &keyuse,sizeof(keyuse));
......
Markdown is supported
0% or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment
GitLab Nexedi Edition | About GitLab | About Nexedi | 沪ICP备2021021310号-2 | 沪ICP备2021021310号-7