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5.0 repository of kgeorge. When kgeorge does a push these changes will
be propagated to the main repository and, within 24 hours after the
push, to the public repository.
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see http://dev.mysql.com/doc/mysql/en/installing-source-tree.html
ChangeSet@stripped, 2007-07-20 20:13:06+03:00, gkodinov@stripped +4 -0
Bug #28591: MySQL need not sort the records in case of
ORDER BY primary_key on InnoDB table
Queries that use an InnoDB secondary index to retrieve
data don't need to sort in case of ORDER BY primary key
if the secondary index is compared to constant(s).
They can also skip sorting if ORDER BY contains both the
the secondary key parts and the primary key parts (in
that order).
This is because InnoDB returns the rows in order of the
primary key for rows with the same values of the secondary
key columns.
Fixed by preventing temp table sort for the qualifying
queries.
mysql-test/r/innodb_mysql.result@stripped, 2007-07-20 20:13:05+03:00, gkodinov@stripped +245 -0
Bug #28591: test case
mysql-test/t/innodb_mysql.test@stripped, 2007-07-20 20:13:05+03:00, gkodinov@stripped +33 -0
Bug #28591: test case
sql/sql_select.cc@stripped, 2007-07-20 20:13:05+03:00, gkodinov@stripped +60 -6
Bug #28591:
1. Use the primary key as suffix when testing
if the key can be used for ORDER BY on
supporting engines.
2. Check if the primary key can be used for
sorting if all the secondary key parts are
constants on supporting engines
sql/table.cc@stripped, 2007-07-20 20:13:05+03:00, gkodinov@stripped +4 -0
Bug #28591: can use the primary key
to sort as well.
diff -Nrup a/mysql-test/r/innodb_mysql.result b/mysql-test/r/innodb_mysql.result
--- a/mysql-test/r/innodb_mysql.result 2007-07-07 22:17:02 +03:00
+++ b/mysql-test/r/innodb_mysql.result 2007-07-20 20:13:05 +03:00
@@ -735,4 +735,249 @@ COUNT(*)
3072
set @@sort_buffer_size=default;
DROP TABLE t1,t2;
+CREATE TABLE t1 (a int, b int, PRIMARY KEY (a), KEY bkey (b)) ENGINE=InnoDB;
+INSERT INTO t1 VALUES (1,2),(3,2),(2,2),(4,2),(5,2),(6,2),(7,2),(8,2);
+INSERT INTO t1 SELECT a + 8, 2 FROM t1;
+INSERT INTO t1 SELECT a + 16, 1 FROM t1;
+EXPLAIN SELECT * FROM t1 WHERE b=2 ORDER BY a;
+id 1
+select_type SIMPLE
+table t1
+type ref
+possible_keys bkey
+key bkey
+key_len 5
+ref const
+rows 16
+Extra Using where; Using index
+SELECT * FROM t1 WHERE b=2 ORDER BY a;
+a b
+1 2
+2 2
+3 2
+4 2
+5 2
+6 2
+7 2
+8 2
+9 2
+10 2
+11 2
+12 2
+13 2
+14 2
+15 2
+16 2
+EXPLAIN SELECT * FROM t1 WHERE b BETWEEN 1 AND 2 ORDER BY a;
+id 1
+select_type SIMPLE
+table t1
+type range
+possible_keys bkey
+key bkey
+key_len 5
+ref NULL
+rows 16
+Extra Using where; Using index; Using filesort
+SELECT * FROM t1 WHERE b BETWEEN 1 AND 2 ORDER BY a;
+a b
+1 2
+2 2
+3 2
+4 2
+5 2
+6 2
+7 2
+8 2
+9 2
+10 2
+11 2
+12 2
+13 2
+14 2
+15 2
+16 2
+17 1
+18 1
+19 1
+20 1
+21 1
+22 1
+23 1
+24 1
+25 1
+26 1
+27 1
+28 1
+29 1
+30 1
+31 1
+32 1
+EXPLAIN SELECT * FROM t1 WHERE b BETWEEN 1 AND 2 ORDER BY b,a;
+id 1
+select_type SIMPLE
+table t1
+type range
+possible_keys bkey
+key bkey
+key_len 5
+ref NULL
+rows 16
+Extra Using where; Using index
+SELECT * FROM t1 WHERE b BETWEEN 1 AND 2 ORDER BY b,a;
+a b
+17 1
+18 1
+19 1
+20 1
+21 1
+22 1
+23 1
+24 1
+25 1
+26 1
+27 1
+28 1
+29 1
+30 1
+31 1
+32 1
+1 2
+2 2
+3 2
+4 2
+5 2
+6 2
+7 2
+8 2
+9 2
+10 2
+11 2
+12 2
+13 2
+14 2
+15 2
+16 2
+CREATE TABLE t2 (a int, b int, c int, PRIMARY KEY (a), KEY bkey (b,c))
+ENGINE=InnoDB;
+INSERT INTO t2 VALUES (1,1,1),(3,1,1),(2,1,1),(4,1,1);
+INSERT INTO t2 SELECT a + 4, 1, 1 FROM t2;
+INSERT INTO t2 SELECT a + 8, 1, 1 FROM t2;
+EXPLAIN SELECT * FROM t2 WHERE b=1 ORDER BY a;
+id 1
+select_type SIMPLE
+table t2
+type ref
+possible_keys bkey
+key bkey
+key_len 5
+ref const
+rows 8
+Extra Using where; Using index; Using filesort
+SELECT * FROM t2 WHERE b=1 ORDER BY a;
+a b c
+1 1 1
+2 1 1
+3 1 1
+4 1 1
+5 1 1
+6 1 1
+7 1 1
+8 1 1
+9 1 1
+10 1 1
+11 1 1
+12 1 1
+13 1 1
+14 1 1
+15 1 1
+16 1 1
+EXPLAIN SELECT * FROM t2 WHERE b=1 AND c=1 ORDER BY a;
+id 1
+select_type SIMPLE
+table t2
+type ref
+possible_keys bkey
+key bkey
+key_len 10
+ref const,const
+rows 8
+Extra Using where; Using index
+SELECT * FROM t2 WHERE b=1 AND c=1 ORDER BY a;
+a b c
+1 1 1
+2 1 1
+3 1 1
+4 1 1
+5 1 1
+6 1 1
+7 1 1
+8 1 1
+9 1 1
+10 1 1
+11 1 1
+12 1 1
+13 1 1
+14 1 1
+15 1 1
+16 1 1
+EXPLAIN SELECT * FROM t2 WHERE b=1 AND c=1 ORDER BY b,c,a;
+id 1
+select_type SIMPLE
+table t2
+type ref
+possible_keys bkey
+key bkey
+key_len 10
+ref const,const
+rows 8
+Extra Using where; Using index
+SELECT * FROM t2 WHERE b=1 AND c=1 ORDER BY b,c,a;
+a b c
+1 1 1
+2 1 1
+3 1 1
+4 1 1
+5 1 1
+6 1 1
+7 1 1
+8 1 1
+9 1 1
+10 1 1
+11 1 1
+12 1 1
+13 1 1
+14 1 1
+15 1 1
+16 1 1
+EXPLAIN SELECT * FROM t2 WHERE b=1 AND c=1 ORDER BY c,a;
+id 1
+select_type SIMPLE
+table t2
+type ref
+possible_keys bkey
+key bkey
+key_len 10
+ref const,const
+rows 8
+Extra Using where; Using index
+SELECT * FROM t2 WHERE b=1 AND c=1 ORDER BY c,a;
+a b c
+1 1 1
+2 1 1
+3 1 1
+4 1 1
+5 1 1
+6 1 1
+7 1 1
+8 1 1
+9 1 1
+10 1 1
+11 1 1
+12 1 1
+13 1 1
+14 1 1
+15 1 1
+16 1 1
+DROP TABLE t1,t2;
End of 5.0 tests
diff -Nrup a/mysql-test/t/innodb_mysql.test b/mysql-test/t/innodb_mysql.test
--- a/mysql-test/t/innodb_mysql.test 2007-07-07 22:19:29 +03:00
+++ b/mysql-test/t/innodb_mysql.test 2007-07-20 20:13:05 +03:00
@@ -741,4 +741,37 @@ set @@sort_buffer_size=default;
DROP TABLE t1,t2;
+#
+# Bug #28591: MySQL need not sort the records in case of ORDER BY
+# primary_key on InnoDB table
+#
+
+CREATE TABLE t1 (a int, b int, PRIMARY KEY (a), KEY bkey (b)) ENGINE=InnoDB;
+INSERT INTO t1 VALUES (1,2),(3,2),(2,2),(4,2),(5,2),(6,2),(7,2),(8,2);
+INSERT INTO t1 SELECT a + 8, 2 FROM t1;
+INSERT INTO t1 SELECT a + 16, 1 FROM t1;
+query_vertical EXPLAIN SELECT * FROM t1 WHERE b=2 ORDER BY a;
+SELECT * FROM t1 WHERE b=2 ORDER BY a;
+query_vertical EXPLAIN SELECT * FROM t1 WHERE b BETWEEN 1 AND 2 ORDER BY a;
+SELECT * FROM t1 WHERE b BETWEEN 1 AND 2 ORDER BY a;
+query_vertical EXPLAIN SELECT * FROM t1 WHERE b BETWEEN 1 AND 2 ORDER BY b,a;
+SELECT * FROM t1 WHERE b BETWEEN 1 AND 2 ORDER BY b,a;
+
+CREATE TABLE t2 (a int, b int, c int, PRIMARY KEY (a), KEY bkey (b,c))
+ ENGINE=InnoDB;
+INSERT INTO t2 VALUES (1,1,1),(3,1,1),(2,1,1),(4,1,1);
+INSERT INTO t2 SELECT a + 4, 1, 1 FROM t2;
+INSERT INTO t2 SELECT a + 8, 1, 1 FROM t2;
+
+query_vertical EXPLAIN SELECT * FROM t2 WHERE b=1 ORDER BY a;
+SELECT * FROM t2 WHERE b=1 ORDER BY a;
+query_vertical EXPLAIN SELECT * FROM t2 WHERE b=1 AND c=1 ORDER BY a;
+SELECT * FROM t2 WHERE b=1 AND c=1 ORDER BY a;
+query_vertical EXPLAIN SELECT * FROM t2 WHERE b=1 AND c=1 ORDER BY b,c,a;
+SELECT * FROM t2 WHERE b=1 AND c=1 ORDER BY b,c,a;
+query_vertical EXPLAIN SELECT * FROM t2 WHERE b=1 AND c=1 ORDER BY c,a;
+SELECT * FROM t2 WHERE b=1 AND c=1 ORDER BY c,a;
+
+DROP TABLE t1,t2;
+
--echo End of 5.0 tests
diff -Nrup a/sql/sql_select.cc b/sql/sql_select.cc
--- a/sql/sql_select.cc 2007-07-12 04:45:22 +03:00
+++ b/sql/sql_select.cc 2007-07-20 20:13:05 +03:00
@@ -12009,6 +12009,7 @@ static int test_if_order_by_key(ORDER *o
key_part_end=key_part+table->key_info[idx].key_parts;
key_part_map const_key_parts=table->const_key_parts[idx];
int reverse=0;
+ my_bool on_primary_key= FALSE;
DBUG_ENTER("test_if_order_by_key");
for (; order ; order=order->next, const_key_parts>>=1)
@@ -12023,7 +12024,30 @@ static int test_if_order_by_key(ORDER *o
for (; const_key_parts & 1 ; const_key_parts>>= 1)
key_part++;
- if (key_part == key_part_end || key_part->field != field)
+ if (key_part == key_part_end)
+ {
+ /*
+ We are at the end of the key. Check if the engine has the primary
+ key as a suffix to the secondary keys. If it has continue to check
+ the primary key as a suffix.
+ */
+ if (!on_primary_key &&
+ (table->file->table_flags() & HA_PRIMARY_KEY_IN_READ_INDEX) &&
+ table->s->primary_key != MAX_KEY)
+ {
+ on_primary_key= TRUE;
+ key_part= table->key_info[table->s->primary_key].key_part;
+ key_part_end=key_part+table->key_info[table->s->primary_key].key_parts;
+ const_key_parts=table->const_key_parts[table->s->primary_key];
+
+ for (; const_key_parts & 1 ; const_key_parts>>= 1)
+ key_part++;
+ }
+ else
+ DBUG_RETURN(0);
+ }
+
+ if (key_part->field != field)
DBUG_RETURN(0);
/* set flag to 1 if we can use read-next on key, else to -1 */
@@ -12034,7 +12058,8 @@ static int test_if_order_by_key(ORDER *o
reverse=flag; // Remember if reverse
key_part++;
}
- *used_key_parts= (uint) (key_part - table->key_info[idx].key_part);
+ *used_key_parts= on_primary_key ? table->key_info[idx].key_parts :
+ (uint) (key_part - table->key_info[idx].key_part);
if (reverse == -1 && !(table->file->index_flags(idx, *used_key_parts-1, 1) &
HA_READ_PREV))
reverse= 0; // Index can't be used
@@ -12341,6 +12366,7 @@ test_if_skip_sort_order(JOIN_TAB *tab,OR
We come here when there is a REF key.
*/
int order_direction;
+ int order_key;
uint used_key_parts;
if (!usable_keys.is_set(ref_key))
{
@@ -12400,10 +12426,38 @@ test_if_skip_sort_order(JOIN_TAB *tab,OR
ref_key= new_ref_key;
}
}
+ order_key= ref_key;
/* Check if we get the rows in requested sorted order by using the key */
- if (usable_keys.is_set(ref_key) &&
- (order_direction = test_if_order_by_key(order,table,ref_key,
- &used_key_parts)))
+ if ((usable_keys.is_set(order_key) &&
+ (order_direction= test_if_order_by_key(order,table,order_key,
+ &used_key_parts))) ||
+ (
+ /*
+ For storage engine that support it (InnoDB) check if we can skip
+ sort queries like :
+ SELECT ... FROM ... WHERE secondary_key = <const>
+ ORDER BY <primary_key>
+ We can skip sorting if :
+ (1) we use REF
+ (2) The storage engine supports it
+ (3) there is a primary key
+ (4) all the subparts of the secondary key are equal to const
+ (5) primary key is usable
+ (6) we have an ORDER BY on the primary key
+ (7) In case we have yes on (1)-(5), use the primary key instead of
+ sorting. The condition is always true : it's the assignment
+ that is important.
+ */
+ order_key == tab->ref.key && // (1)
+ (table->file->table_flags() & HA_PRIMARY_KEY_IN_READ_INDEX) && // (2)
+ table->s->primary_key != MAX_KEY && // (3)
+ ref_key_parts == table->key_info[order_key].key_parts && // (4)
+ usable_keys.is_set(table->s->primary_key) && // (5)
+ (order_direction= test_if_order_by_key(order,table,
+ table->s->primary_key,
+ &used_key_parts)) && // (6)
+ (order_key= table->s->primary_key) >= 0) // (7)
+ )
{
if (order_direction == -1) // If ORDER BY ... DESC
{
@@ -12434,7 +12488,7 @@ test_if_skip_sort_order(JOIN_TAB *tab,OR
}
DBUG_RETURN(1);
}
- if (tab->ref.key_parts < used_key_parts)
+ if (order_key == ref_key && tab->ref.key_parts < used_key_parts)
{
/*
SELECT * FROM t1 WHERE a=1 ORDER BY a DESC,b DESC
diff -Nrup a/sql/table.cc b/sql/table.cc
--- a/sql/table.cc 2007-06-27 14:35:48 +03:00
+++ b/sql/table.cc 2007-07-20 20:13:05 +03:00
@@ -780,7 +780,11 @@ int openfrm(THD *thd, const char *name,
the primary key, then we can use any key to find this column
*/
if (ha_option & HA_PRIMARY_KEY_IN_READ_INDEX)
+ {
field->part_of_key= share->keys_in_use;
+ if (field->part_of_sortkey.is_set(key))
+ field->part_of_sortkey= share->keys_in_use;
+ }
}
if (field->key_length() != key_part->length)
{
| Thread |
|---|
| • bk commit into 5.0 tree (gkodinov:1.2530) BUG#28591 | kgeorge | 20 Jul |
