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| author | igor@olga.mysql.com <> | 2007-08-02 12:45:56 -0700 |
|---|---|---|
| committer | igor@olga.mysql.com <> | 2007-08-02 12:45:56 -0700 |
| commit | cf39429295846cf944e3fd1a327c554ebd08942d (patch) | |
| tree | cb69ff6598e568046e57c591baf10d4a49f2d5b7 /mysql-test/r/select_found.result | |
| parent | 642b0c00ed99334a5540839c0e6598d7a26c8ac7 (diff) | |
| download | mariadb-git-cf39429295846cf944e3fd1a327c554ebd08942d.tar.gz | |
Fixed bug#28404.
This patch adds cost estimation for the queries with ORDER BY / GROUP BY
and LIMIT.
If there was a ref/range access to the table whose rows were required
to be ordered in the result set the optimizer always employed this access
though a scan by a different index that was compatible with the required
order could be cheaper to produce the first L rows of the result set.
Now for such queries the optimizer makes a choice between the cheapest
ref/range accesses not compatible with the given order and index scans
compatible with it.
Diffstat (limited to 'mysql-test/r/select_found.result')
| -rw-r--r-- | mysql-test/r/select_found.result | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/mysql-test/r/select_found.result b/mysql-test/r/select_found.result index 7abd65beb46..7896f8a9f4e 100644 --- a/mysql-test/r/select_found.result +++ b/mysql-test/r/select_found.result @@ -84,7 +84,7 @@ UNIQUE KEY e_n (email,name) EXPLAIN SELECT SQL_CALC_FOUND_ROWS DISTINCT email FROM t2 LEFT JOIN t1 ON kid = t2.id WHERE t1.id IS NULL LIMIT 10; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 system PRIMARY,kid NULL NULL NULL 0 const row not found -1 SIMPLE t2 index NULL e_n 104 NULL 200 +1 SIMPLE t2 index NULL e_n 104 NULL 10 SELECT SQL_CALC_FOUND_ROWS DISTINCT email FROM t2 LEFT JOIN t1 ON kid = t2.id WHERE t1.id IS NULL LIMIT 10; email email1 |