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Indexes can be used for optimization if the operation

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collation is the same with the index collation.
This commit is contained in:
unknown
2004-02-02 17:50:14 +04:00
parent c91c1470c8
commit 65534b77a1
6 changed files with 153 additions and 34 deletions
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47
mysql-test/r/ctype_collate.result
View File

@ -541,3 +541,50 @@ s2 CHAR(5) COLLATE latin1_swedish_ci);
SELECT * FROM t1 WHERE s1 = s2;
ERROR HY000: Illegal mix of collations (latin1_german1_ci,IMPLICIT) and (latin1_swedish_ci,IMPLICIT) for operation '='
DROP TABLE t1;
SET NAMES latin1;
CREATE TABLE t1
(s1 char(10) COLLATE latin1_german1_ci,
s2 char(10) COLLATE latin1_swedish_ci,
KEY(s1),
KEY(s2));
INSERT INTO t1 VALUES ('a','a');
INSERT INTO t1 VALUES ('b','b');
INSERT INTO t1 VALUES ('c','c');
INSERT INTO t1 VALUES ('d','d');
INSERT INTO t1 VALUES ('e','e');
INSERT INTO t1 VALUES ('f','f');
INSERT INTO t1 VALUES ('g','g');
INSERT INTO t1 VALUES ('h','h');
INSERT INTO t1 VALUES ('i','i');
INSERT INTO t1 VALUES ('j','j');
EXPLAIN SELECT * FROM t1 WHERE s1='a';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref s1 s1 11 const 1 Using where
EXPLAIN SELECT * FROM t1 WHERE s2='a';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref s2 s2 11 const 1 Using where
EXPLAIN SELECT * FROM t1 WHERE s1='a' COLLATE latin1_german1_ci;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref s1 s1 11 const 1 Using where
EXPLAIN SELECT * FROM t1 WHERE s2='a' COLLATE latin1_german1_ci;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL s2 NULL NULL NULL 10 Using where
EXPLAIN SELECT * FROM t1 WHERE s1 BETWEEN 'a' AND 'b' COLLATE latin1_german1_ci;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range s1 s1 11 NULL 2 Using where
EXPLAIN SELECT * FROM t1 WHERE s2 BETWEEN 'a' AND 'b' COLLATE latin1_german1_ci;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL s2 NULL NULL NULL 10 Using where
EXPLAIN SELECT * FROM t1 WHERE s1 IN ('a','b' COLLATE latin1_german1_ci);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range s1 s1 11 NULL 2 Using where
EXPLAIN SELECT * FROM t1 WHERE s2 IN ('a','b' COLLATE latin1_german1_ci);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL s2 NULL NULL NULL 10 Using where
EXPLAIN SELECT * FROM t1 WHERE s1 LIKE 'a' COLLATE latin1_german1_ci;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range s1 s1 11 NULL 1 Using where
EXPLAIN SELECT * FROM t1 WHERE s2 LIKE 'a' COLLATE latin1_german1_ci;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL s2 NULL NULL NULL 10 Using where
DROP TABLE t1;

38
mysql-test/t/ctype_collate.test
View File

@ -156,3 +156,41 @@ CREATE TABLE t1
--error 1266
SELECT * FROM t1 WHERE s1 = s2;
DROP TABLE t1;
#
# Test that optimizer doesn't use indexes with wrong collation
#
SET NAMES latin1;
CREATE TABLE t1
(s1 char(10) COLLATE latin1_german1_ci,
s2 char(10) COLLATE latin1_swedish_ci,
KEY(s1),
KEY(s2));
INSERT INTO t1 VALUES ('a','a');
INSERT INTO t1 VALUES ('b','b');
INSERT INTO t1 VALUES ('c','c');
INSERT INTO t1 VALUES ('d','d');
INSERT INTO t1 VALUES ('e','e');
INSERT INTO t1 VALUES ('f','f');
INSERT INTO t1 VALUES ('g','g');
INSERT INTO t1 VALUES ('h','h');
INSERT INTO t1 VALUES ('i','i');
INSERT INTO t1 VALUES ('j','j');
EXPLAIN SELECT * FROM t1 WHERE s1='a';
EXPLAIN SELECT * FROM t1 WHERE s2='a';
EXPLAIN SELECT * FROM t1 WHERE s1='a' COLLATE latin1_german1_ci;
EXPLAIN SELECT * FROM t1 WHERE s2='a' COLLATE latin1_german1_ci;
EXPLAIN SELECT * FROM t1 WHERE s1 BETWEEN 'a' AND 'b' COLLATE latin1_german1_ci;
EXPLAIN SELECT * FROM t1 WHERE s2 BETWEEN 'a' AND 'b' COLLATE latin1_german1_ci;
EXPLAIN SELECT * FROM t1 WHERE s1 IN ('a','b' COLLATE latin1_german1_ci);
EXPLAIN SELECT * FROM t1 WHERE s2 IN ('a','b' COLLATE latin1_german1_ci);
EXPLAIN SELECT * FROM t1 WHERE s1 LIKE 'a' COLLATE latin1_german1_ci;
EXPLAIN SELECT * FROM t1 WHERE s2 LIKE 'a' COLLATE latin1_german1_ci;
DROP TABLE t1;

1
sql/item.h
View File

@ -204,6 +204,7 @@ public:
virtual Item *get_tmp_table_item(THD *thd) { return copy_or_same(thd); }
CHARSET_INFO *default_charset() const;
virtual CHARSET_INFO *compare_collation() { return NULL; }
virtual bool walk(Item_processor processor, byte *arg)
{

7
sql/item_cmpfunc.h
View File

@ -191,6 +191,7 @@ public:
bool have_rev_func() const { return rev_functype() != UNKNOWN_FUNC; }
void print(String *str) { Item_func::print_op(str); }
bool is_null() { return test(args[0]->is_null() || args[1]->is_null()); }
CHARSET_INFO *compare_collation() { return cmp.cmp_collation.collation; }
friend class Arg_comparator;
};
@ -340,6 +341,7 @@ public:
const char *func_name() const { return "between"; }
void fix_length_and_dec();
void print(String *str);
CHARSET_INFO *compare_collation() { return cmp_collation.collation; }
};
@ -479,6 +481,7 @@ public:
const char *func_name() const { return "case"; }
void print(String *str);
Item *find_item(String *str);
CHARSET_INFO *compare_collation() { return cmp_collation.collation; }
};
@ -726,6 +729,7 @@ class Item_func_in :public Item_int_func
enum Functype functype() const { return IN_FUNC; }
const char *func_name() const { return " IN "; }
bool nulls_in_row();
CHARSET_INFO *compare_collation() { return cmp_collation.collation; }
};
/* Functions used by where clause */
@ -766,6 +770,7 @@ public:
table_map not_null_tables() const { return 0; }
optimize_type select_optimize() const { return OPTIMIZE_NULL; }
Item *neg_transformer();
CHARSET_INFO *compare_collation() { return args[0]->collation.collation; }
};
/* Functions used by HAVING for rewriting IN subquery */
@ -800,6 +805,7 @@ public:
table_map not_null_tables() const { return 0; }
Item *neg_transformer();
void print(String *str);
CHARSET_INFO *compare_collation() { return args[0]->collation.collation; }
};
@ -854,6 +860,7 @@ public:
bool fix_fields(THD *thd, struct st_table_list *tlist, Item **ref);
const char *func_name() const { return "regexp"; }
void print(String *str) { print_op(str); }
CHARSET_INFO *compare_collation() { return cmp_collation.collation; }
};
#else

71
sql/opt_range.cc
View File

@ -291,10 +291,11 @@ typedef struct st_qsel_param {
bool quick; // Don't calulate possible keys
} PARAM;
static SEL_TREE * get_mm_parts(PARAM *param,Field *field,
static SEL_TREE * get_mm_parts(PARAM *param,COND *cond_func,Field *field,
Item_func::Functype type,Item *value,
Item_result cmp_type);
static SEL_ARG *get_mm_leaf(PARAM *param,Field *field,KEY_PART *key_part,
static SEL_ARG *get_mm_leaf(PARAM *param,COND *cond_func,Field *field,
KEY_PART *key_part,
Item_func::Functype type,Item *value);
static SEL_TREE *get_mm_tree(PARAM *param,COND *cond);
static ha_rows check_quick_select(PARAM *param,uint index,SEL_ARG *key_tree);
@ -834,10 +835,10 @@ static SEL_TREE *get_mm_tree(PARAM *param,COND *cond)
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, field,
get_mm_parts(param, cond_func, field,
Item_func::GE_FUNC,
cond_func->arguments()[1], cmp_type),
get_mm_parts(param, field,
get_mm_parts(param, cond_func, field,
Item_func::LE_FUNC,
cond_func->arguments()[2], cmp_type)));
}
@ -850,13 +851,14 @@ static SEL_TREE *get_mm_tree(PARAM *param,COND *cond)
{
Field *field=((Item_field*) (func->key_item()))->field;
Item_result cmp_type=field->cmp_type();
tree= get_mm_parts(param,field,Item_func::EQ_FUNC,
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++)
{
SEL_TREE *new_tree=get_mm_parts(param,field,Item_func::EQ_FUNC,
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);
}
@ -875,7 +877,7 @@ static SEL_TREE *get_mm_tree(PARAM *param,COND *cond)
/* 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,
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] :
@ -888,7 +890,7 @@ static SEL_TREE *get_mm_tree(PARAM *param,COND *cond)
cond_func->have_rev_func() &&
cond_func->arguments()[1]->type() == Item::FIELD_ITEM)
{
DBUG_RETURN(get_mm_parts(param,
DBUG_RETURN(get_mm_parts(param, cond_func,
((Item_field*)
(cond_func->arguments()[1]))->field,
((Item_bool_func2*) cond_func)->rev_functype(),
@ -902,7 +904,8 @@ static SEL_TREE *get_mm_tree(PARAM *param,COND *cond)
static SEL_TREE *
get_mm_parts(PARAM *param, Field *field, Item_func::Functype type,
get_mm_parts(PARAM *param, COND *cond_func, Field *field,
Item_func::Functype type,
Item *value, Item_result cmp_type)
{
bool ne_func= FALSE;
@ -931,7 +934,8 @@ get_mm_parts(PARAM *param, Field *field, Item_func::Functype type,
DBUG_RETURN(0); // OOM
if (!value || !(value->used_tables() & ~param->read_tables))
{
sel_arg=get_mm_leaf(param,key_part->field,key_part,type,value);
sel_arg=get_mm_leaf(param,cond_func,
key_part->field,key_part,type,value);
if (!sel_arg)
continue;
if (sel_arg->type == SEL_ARG::IMPOSSIBLE)
@ -953,7 +957,8 @@ get_mm_parts(PARAM *param, Field *field, Item_func::Functype type,
if (ne_func)
{
SEL_TREE *tree2= get_mm_parts(param, field, Item_func::GT_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);
@ -963,7 +968,7 @@ get_mm_parts(PARAM *param, Field *field, Item_func::Functype type,
static SEL_ARG *
get_mm_leaf(PARAM *param, Field *field, KEY_PART *key_part,
get_mm_leaf(PARAM *param, COND *conf_func, Field *field, KEY_PART *key_part,
Item_func::Functype type,Item *value)
{
uint maybe_null=(uint) field->real_maybe_null(), copies;
@ -972,6 +977,32 @@ get_mm_leaf(PARAM *param, Field *field, KEY_PART *key_part,
char *str, *str2;
DBUG_ENTER("get_mm_leaf");
if (!value) // IS NULL or IS NOT NULL
{
if (field->table->outer_join) // Can't use a key on this
DBUG_RETURN(0);
if (!maybe_null) // Not null field
DBUG_RETURN(type == Item_func::ISNULL_FUNC ? &null_element : 0);
if (!(tree=new SEL_ARG(field,is_null_string,is_null_string)))
DBUG_RETURN(0); // out of memory
if (type == Item_func::ISNOTNULL_FUNC)
{
tree->min_flag=NEAR_MIN; /* IS NOT NULL -> X > NULL */
tree->max_flag=NO_MAX_RANGE;
}
DBUG_RETURN(tree);
}
/*
We can't use an index when comparing stings of
different collations
*/
if (field->result_type() == STRING_RESULT &&
value->result_type() == STRING_RESULT &&
key_part->image_type == Field::itRAW &&
((Field_str*)field)->charset() != conf_func->compare_collation())
DBUG_RETURN(0);
if (type == Item_func::LIKE_FUNC)
{
bool like_error;
@ -1035,22 +1066,6 @@ get_mm_leaf(PARAM *param, Field *field, KEY_PART *key_part,
DBUG_RETURN(new SEL_ARG(field,min_str,max_str));
}
if (!value) // IS NULL or IS NOT NULL
{
if (field->table->outer_join) // Can't use a key on this
DBUG_RETURN(0);
if (!maybe_null) // Not null field
DBUG_RETURN(type == Item_func::ISNULL_FUNC ? &null_element : 0);
if (!(tree=new SEL_ARG(field,is_null_string,is_null_string)))
DBUG_RETURN(0); // out of memory
if (type == Item_func::ISNOTNULL_FUNC)
{
tree->min_flag=NEAR_MIN; /* IS NOT NULL -> X > NULL */
tree->max_flag=NO_MAX_RANGE;
}
DBUG_RETURN(tree);
}
if (!field->optimize_range(param->real_keynr[key_part->key]) &&
type != Item_func::EQ_FUNC &&
type != Item_func::EQUAL_FUNC)

21
sql/sql_select.cc
View File

@ -2131,7 +2131,7 @@ merge_key_fields(KEY_FIELD *start,KEY_FIELD *new_fields,KEY_FIELD *end,
*/
static void
add_key_field(KEY_FIELD **key_fields,uint and_level,
add_key_field(KEY_FIELD **key_fields,uint and_level, COND *cond,
Field *field,bool eq_func,Item **value, uint num_values,
table_map usable_tables)
{
@ -2198,6 +2198,17 @@ add_key_field(KEY_FIELD **key_fields,uint and_level,
(*value)->result_type() != STRING_RESULT &&
field->cmp_type() != (*value)->result_type())
return;
/*
We can't use indexes if the effective collation
of the operation differ from the field collation.
*/
if (field->result_type() == STRING_RESULT &&
(*value)->result_type() == STRING_RESULT &&
field->cmp_type() == STRING_RESULT &&
((Field_str*)field)->charset() != cond->compare_collation())
return;
}
}
DBUG_ASSERT(num_values == 1);
@ -2261,7 +2272,7 @@ add_key_fields(JOIN_TAB *stat,KEY_FIELD **key_fields,uint *and_level,
// BETWEEN or IN
if (cond_func->key_item()->real_item()->type() == Item::FIELD_ITEM &&
!(cond_func->used_tables() & OUTER_REF_TABLE_BIT))
add_key_field(key_fields,*and_level,
add_key_field(key_fields,*and_level,cond_func,
((Item_field*) (cond_func->key_item()->real_item()))->
field, 0,
cond_func->arguments()+1, cond_func->argument_count()-1,
@ -2275,7 +2286,7 @@ add_key_fields(JOIN_TAB *stat,KEY_FIELD **key_fields,uint *and_level,
if (cond_func->arguments()[0]->real_item()->type() == Item::FIELD_ITEM &&
!(cond_func->arguments()[0]->used_tables() & OUTER_REF_TABLE_BIT))
{
add_key_field(key_fields,*and_level,
add_key_field(key_fields,*and_level,cond_func,
((Item_field*) (cond_func->arguments()[0])->real_item())
->field,
equal_func,
@ -2285,7 +2296,7 @@ add_key_fields(JOIN_TAB *stat,KEY_FIELD **key_fields,uint *and_level,
cond_func->functype() != Item_func::LIKE_FUNC &&
!(cond_func->arguments()[1]->used_tables() & OUTER_REF_TABLE_BIT))
{
add_key_field(key_fields,*and_level,
add_key_field(key_fields,*and_level,cond_func,
((Item_field*) (cond_func->arguments()[1])->real_item())
->field,
equal_func,
@ -2301,7 +2312,7 @@ add_key_fields(JOIN_TAB *stat,KEY_FIELD **key_fields,uint *and_level,
Item *tmp=new Item_null;
if (!tmp) // Should never be true
return;
add_key_field(key_fields,*and_level,
add_key_field(key_fields,*and_level,cond_func,
((Item_field*) (cond_func->arguments()[0])->real_item())
->field,
cond_func->functype() == Item_func::ISNULL_FUNC,