MySQL Bugs: #8617: SQL_CALC_FOUND_ROWS with rollup , affect limit

Bug #8617	SQL_CALC_FOUND_ROWS with rollup , affect limit
Submitted:	19 Feb 2005 2:06	Modified:	21 Mar 2005 20:04
Reporter:	Martin Friebe (Gold Quality Contributor) (OCA)	Email Updates:
Status:	Closed	Impact on me:	None
Category:	MySQL Server	Severity:	S3 (Non-critical)
Version:	4.1.10	OS:
Assigned to:	Igor Babaev	CPU Architecture:	Any

Description:
according to the doc limit is applied after rollup. This seems to work, but it breaks, when using SQL_CLAC_FOUND_ROWS.

see example

How to repeat:
create table x (a integer, b integer);
insert into x values (1,4), (2,2),(2,2), (4,1),(4,1),(4,1),(4,1);

# this is fine
 select  SQL_CALC_FOUND_ROWS  a, sum(b) from x group by a  limit 1;
+------+--------+
| a    | sum(b) |
+------+--------+
|    1 |      4 |
+------+--------+
1 row in set (0.00 sec)

# this is also fine
select   a, sum(b) from x group by a with rollup  limit 1;
+------+--------+
| a    | sum(b) |
+------+--------+
|    1 |      4 |
+------+--------+
1 row in set (0.01 sec)

# and this returns the rollup, even so its clearly outside the limit
 select  SQL_CALC_FOUND_ROWS  a, sum(b) from x group by a with rollup  limit 1;
+------+--------+
| a    | sum(b) |
+------+--------+
|    1 |      4 |
| NULL |     12 |
+------+--------+
2 rows in set (0.00 sec)

Suggested fix:
-

A patch for this bug has been committed. After review, it may
be pushed to the relevant source trees for release in the next
version. You can access the patch from:

  http://lists.mysql.com/internals/23168

The fix for this bug will appear in 4.1.11 and 5.0.4 (or even in 5.0.3)
The chanset for the fix for 4.1 was merged into 5.0.

ChangeSet
  1.2134 05/03/17 20:18:19 igor@rurik.mysql.com +3 -0
  olap.test:
    Added a test case for bug #8617.
  sql_select.cc:
    Fixed bug #8617.
    Queries with ROLLUP and LIMIT n returned more than n rows
    if SQL_CALC_FOUND_ROWS was used.

Noted in 4.1.11, 5.0.4 changelogs.