From 95a8c6c327a477c3bcaf67ba6acf7f48bbab4158 Mon Sep 17 00:00:00 2001 From: unknown Date: Fri, 20 Jul 2007 21:05:29 +0300 Subject: 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: Bug #28591: test case mysql-test/t/innodb_mysql.test: Bug #28591: test case sql/sql_select.cc: Bug #28591: Use the primary key as suffix when testing if the key can be used for ORDER BY on supporting engines. sql/table.cc: Bug #28591: can use the primary key as a suffix for the secondary keys --- mysql-test/t/innodb_mysql.test | 33 +++++++++++++++++++++++++++++++++ 1 file changed, 33 insertions(+) (limited to 'mysql-test/t/innodb_mysql.test') diff --git a/mysql-test/t/innodb_mysql.test b/mysql-test/t/innodb_mysql.test index d4ce997ddb1..9a44c673548 100644 --- a/mysql-test/t/innodb_mysql.test +++ b/mysql-test/t/innodb_mysql.test @@ -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 -- cgit v1.2.1