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BUG#46961 - archive engine loses rows during self joining select!

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SELECT with join (not only self-join) from archive table may
return incomplete result set, when result set size exceeds
join buffer size.

The problem was that archive row counter was initialzed too
early, when ha_archive::info() method was called. Later,
when optimizer exceeds join buffer, it attempts to reuse
handler without calling ha_archive::info() again (which is
correct).

Fixed by moving row counter initialization from
ha_archive::info() to ha_archive::rnd_init().

mysql-test/r/archive.result:
  A test case for BUG#46961.
mysql-test/t/archive.test:
  A test case for BUG#46961.
storage/archive/ha_archive.cc:
  Since a cursor may get reused without a call to ::info(),
  move assignment of scan_rows to a proper place, that is
  ::rnd_init().
This commit is contained in:
Sergey Vojtovich
2009-09-04 12:29:18 +05:00
parent 9776b6f9cd
commit a7de205747
3 changed files with 25 additions and 1 deletions
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11
mysql-test/r/archive.result
View File

@ -12695,3 +12695,14 @@ a b
1 NULL 1 NULL
2 NULL 2 NULL
DROP TABLE t1; DROP TABLE t1;
SET @save_join_buffer_size= @@join_buffer_size;
SET @@join_buffer_size= 8228;
CREATE TABLE t1(a CHAR(255)) ENGINE=archive;
INSERT INTO t1 VALUES('aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa'),
('aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa'),
('aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa');
SELECT COUNT(t1.a) FROM t1, t1 a, t1 b, t1 c, t1 d, t1 e;
COUNT(t1.a)
729
DROP TABLE t1;
SET @@join_buffer_size= @save_join_buffer_size;

13
mysql-test/t/archive.test
View File

@ -1599,3 +1599,16 @@ INSERT INTO t1 VALUES (NULL, NULL),(NULL, NULL);
FLUSH TABLE t1; FLUSH TABLE t1;
SELECT * FROM t1 ORDER BY a; SELECT * FROM t1 ORDER BY a;
DROP TABLE t1; DROP TABLE t1;
#
# BUG#46961 - archive engine loses rows during self joining select!
#
SET @save_join_buffer_size= @@join_buffer_size;
SET @@join_buffer_size= 8228;
CREATE TABLE t1(a CHAR(255)) ENGINE=archive;
INSERT INTO t1 VALUES('aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa'),
('aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa'),
('aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa');
SELECT COUNT(t1.a) FROM t1, t1 a, t1 b, t1 c, t1 d, t1 e;
DROP TABLE t1;
SET @@join_buffer_size= @save_join_buffer_size;

2
storage/archive/ha_archive.cc
View File

@ -993,6 +993,7 @@ int ha_archive::rnd_init(bool scan)
/* We rewind the file so that we can read from the beginning if scan */ /* We rewind the file so that we can read from the beginning if scan */
if (scan) if (scan)
{ {
scan_rows= stats.records;
DBUG_PRINT("info", ("archive will retrieve %llu rows", DBUG_PRINT("info", ("archive will retrieve %llu rows",
(unsigned long long) scan_rows)); (unsigned long long) scan_rows));
@ -1461,7 +1462,6 @@ int ha_archive::info(uint flag)
stats.records= share->rows_recorded; stats.records= share->rows_recorded;
pthread_mutex_unlock(&share->mutex); pthread_mutex_unlock(&share->mutex);
scan_rows= stats.records;
stats.deleted= 0; stats.deleted= 0;
DBUG_PRINT("ha_archive", ("Stats rows is %d\n", (int)stats.records)); DBUG_PRINT("ha_archive", ("Stats rows is %d\n", (int)stats.records));