BUG#14940 "MySQL choose wrong index", v.2

- Make the range-et-al optimizer produce E(#table records after table 
                                           condition is applied),
- Make the join optimizer use this value,
- Add "filtered" column to EXPLAIN EXTENDED to show 
  fraction of records left after table condition is applied
- Adjust test results, add comments

1 files changed, 6 insertions, 6 deletions

diff --git a/mysql-test/r/case.result b/mysql-test/r/case.result
index 1d2041432fe..9ee64ee6dbd 100644
--- a/mysql-test/r/case.result
+++ b/mysql-test/r/case.result
@@ -24,8 +24,8 @@ select CASE 1 when 1 then "one" WHEN 2 then "two" ELSE "more" END;
 CASE 1 when 1 then "one" WHEN 2 then "two" ELSE "more" END
 one
 explain extended select CASE 1 when 1 then "one" WHEN 2 then "two" ELSE "more" END;
-id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	No tables used
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
+1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	NULL	No tables used
 Warnings:
 Note	1003	select (case 1 when 1 then _latin1'one' when 2 then _latin1'two' else _latin1'more' end) AS `CASE 1 when 1 then "one" WHEN 2 then "two" ELSE "more" END`
 select CASE 2.0 when 1 then "one" WHEN 2.0 then "two" ELSE "more" END;
@@ -63,8 +63,8 @@ fcase	count(*)
 2	1
 3	1
 explain extended select case a when 1 then 2 when 2 then 3 else 0 end as fcase, count(*) from t1 group by fcase;
-id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	4	Using temporary; Using filesort
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	4	100.00	Using temporary; Using filesort
 Warnings:
 Note	1003	select (case `test`.`t1`.`a` when 1 then 2 when 2 then 3 else 0 end) AS `fcase`,count(0) AS `count(*)` from `test`.`t1` group by (case `test`.`t1`.`a` when 1 then 2 when 2 then 3 else 0 end)
 select case a when 1 then "one" when 2 then "two" else "nothing" end as fcase, count(*) from t1 group by fcase;
@@ -144,8 +144,8 @@ explain extended SELECT
 COALESCE(1), COALESCE(1.0),COALESCE('a'),
 COALESCE(1,1.0), COALESCE(1,'1'),COALESCE(1.1,'1'),
 COALESCE('a' COLLATE latin1_bin,'b');
-id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	No tables used
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
+1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	NULL	No tables used
 Warnings:
 Note	1003	select coalesce(1) AS `COALESCE(1)`,coalesce(1.0) AS `COALESCE(1.0)`,coalesce(_latin1'a') AS `COALESCE('a')`,coalesce(1,1.0) AS `COALESCE(1,1.0)`,coalesce(1,_latin1'1') AS `COALESCE(1,'1')`,coalesce(1.1,_latin1'1') AS `COALESCE(1.1,'1')`,coalesce((_latin1'a' collate latin1_bin),_latin1'b') AS `COALESCE('a' COLLATE latin1_bin,'b')`
 SHOW CREATE TABLE t1;