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|
# REPAIR USE_FRM is not implemented for partitioned tables.
# Test what happens if we exchange a crashed partition with a table
SHOW VARIABLES LIKE 'myisam_recover_options';
Variable_name Value
myisam_recover_options OFF
CREATE TABLE t (a INT, KEY (a)) ENGINE=MyISAM;
CREATE TABLE tp (a INT, KEY (a)) ENGINE=MyISAM
PARTITION BY RANGE (a)
(PARTITION pCrashed VALUES LESS THAN (15),
PARTITION pMAX VALUES LESS THAN MAXVALUE);
INSERT INTO t VALUES (1), (2), (3), (4), (5), (6), (7), (8), (9), (10), (11);
INSERT INTO tp VALUES (1), (2), (3), (4), (5), (6), (7), (8), (9), (10), (11);
FLUSH TABLES;
# replacing tp#P#pCrashed.MYI with a corrupt + unclosed one created by doing:
# 'create table t1 (a int key(a))' head -c1024 t1.MYI > corrupt_t1.MYI
CHECK TABLE tp;
Table Op Msg_type Msg_text
test.tp check warning 1 client is using or hasn't closed the table properly
test.tp check error Size of indexfile is: 1024 Should be: 2048
test.tp check warning Size of datafile is: 77 Should be: 7
test.tp check error Partition pCrashed returned error
test.tp check error Corrupt
ALTER TABLE tp EXCHANGE PARTITION pCrashed WITH TABLE t;
ERROR HY000: Table './test/tp#P#pCrashed' is marked as crashed and should be repaired
REPAIR TABLE tp;
Table Op Msg_type Msg_text
test.tp repair warning Number of rows changed from 1 to 11
test.tp repair status OK
CHECK TABLE tp;
Table Op Msg_type Msg_text
test.tp check status OK
ALTER TABLE tp EXCHANGE PARTITION pCrashed WITH TABLE t;
CHECK TABLE t;
Table Op Msg_type Msg_text
test.t check status OK
CHECK TABLE tp;
Table Op Msg_type Msg_text
test.tp check status OK
FLUSH TABLES;
CHECK TABLE t;
Table Op Msg_type Msg_text
test.t check warning 1 client is using or hasn't closed the table properly
test.t check error Size of indexfile is: 1024 Should be: 2048
test.t check warning Size of datafile is: 77 Should be: 7
test.t check error Corrupt
ALTER TABLE tp EXCHANGE PARTITION pCrashed WITH TABLE t;
ERROR HY000: Table './test/t' is marked as crashed and should be repaired
REPAIR TABLE t;
Table Op Msg_type Msg_text
test.t repair warning Number of rows changed from 1 to 11
test.t repair status OK
CHECK TABLE t;
Table Op Msg_type Msg_text
test.t check status OK
ALTER TABLE tp EXCHANGE PARTITION pCrashed WITH TABLE t;
CHECK TABLE tp;
Table Op Msg_type Msg_text
test.tp check status OK
CHECK TABLE t;
Table Op Msg_type Msg_text
test.t check status OK
DROP TABLE t, tp;
# test of non partitioned myisam for reference
CREATE TABLE t1_will_crash (a INT, KEY (a)) ENGINE=MyISAM;
INSERT INTO t1_will_crash VALUES (1), (2), (3), (4), (5), (6), (7), (8), (9), (10), (11);
FLUSH TABLES;
# replacing t1.MYI with a corrupt + unclosed one created by doing:
# 'create table t1 (a int key(a))' head -c1024 t1.MYI > corrupt_t1.MYI
CHECK TABLE t1_will_crash;
Table Op Msg_type Msg_text
test.t1_will_crash check warning 1 client is using or hasn't closed the table properly
test.t1_will_crash check error Size of indexfile is: 1024 Should be: 2048
test.t1_will_crash check warning Size of datafile is: 77 Should be: 7
test.t1_will_crash check error Corrupt
REPAIR TABLE t1_will_crash;
Table Op Msg_type Msg_text
test.t1_will_crash repair warning Number of rows changed from 1 to 11
test.t1_will_crash repair status OK
SELECT * FROM t1_will_crash;
a
1
2
3
4
5
6
7
8
9
10
11
DROP TABLE t1_will_crash;
# test of check/repair of a damaged partition's MYI-file
CREATE TABLE t1_will_crash (a INT, KEY (a))
ENGINE=MyISAM
PARTITION BY HASH (a)
PARTITIONS 3;
INSERT INTO t1_will_crash VALUES (1), (2), (3), (4), (5), (6), (7), (8), (9), (10), (11);
FLUSH TABLES;
# test with CHECK/REPAIR TABLE
# replacing t1#P#p1.MYI with a corrupt + unclosed one created by doing:
# 'create table t1 (a int key(a)) partition by hash (a) partitions 3'
# head -c1024 t1#P#p1.MYI > corrupt_t1#P#p1.MYI
CHECK TABLE t1_will_crash;
Table Op Msg_type Msg_text
test.t1_will_crash check warning 1 client is using or hasn't closed the table properly
test.t1_will_crash check error Size of indexfile is: 1024 Should be: 2048
test.t1_will_crash check warning Size of datafile is: 28 Should be: 7
test.t1_will_crash check error Partition p1 returned error
test.t1_will_crash check error Corrupt
REPAIR TABLE t1_will_crash;
Table Op Msg_type Msg_text
test.t1_will_crash repair warning Number of rows changed from 1 to 4
test.t1_will_crash repair status OK
SELECT * FROM t1_will_crash;
a
1
2
3
4
5
6
7
8
9
10
11
FLUSH TABLES;
# test with ALTER TABLE ... CHECK/REPAIR PARTITION
# replacing t1_will_crash#P#p1.MYI with a corrupt + unclosed one
ALTER TABLE t1_will_crash CHECK PARTITION p0, p2;
Table Op Msg_type Msg_text
test.t1_will_crash check status OK
ALTER TABLE t1_will_crash CHECK PARTITION p0, p1;
Table Op Msg_type Msg_text
test.t1_will_crash check warning 1 client is using or hasn't closed the table properly
test.t1_will_crash check error Size of indexfile is: 1024 Should be: 2048
test.t1_will_crash check warning Size of datafile is: 28 Should be: 7
test.t1_will_crash check error Partition p1 returned error
test.t1_will_crash check error Corrupt
ALTER TABLE t1_will_crash CHECK PARTITION p1, p2;
Table Op Msg_type Msg_text
test.t1_will_crash check warning Table is marked as crashed
test.t1_will_crash check warning 1 client is using or hasn't closed the table properly
test.t1_will_crash check error Size of indexfile is: 1024 Should be: 2048
test.t1_will_crash check warning Size of datafile is: 28 Should be: 7
test.t1_will_crash check error Partition p1 returned error
test.t1_will_crash check error Corrupt
ALTER TABLE t1_will_crash REPAIR PARTITION p0, p2;
Table Op Msg_type Msg_text
test.t1_will_crash repair status OK
ALTER TABLE t1_will_crash REPAIR PARTITION p0, p1;
Table Op Msg_type Msg_text
test.t1_will_crash repair warning Number of rows changed from 1 to 4
test.t1_will_crash repair status OK
SELECT * FROM t1_will_crash;
a
1
2
3
4
5
6
7
8
9
10
11
DROP TABLE t1_will_crash;
# test of check/repair of a damaged subpartition's MYI-file
CREATE TABLE t1_will_crash (a INT, KEY (a))
ENGINE=MyISAM
PARTITION BY RANGE (a)
SUBPARTITION BY HASH (a)
SUBPARTITIONS 2
(PARTITION p0 VALUES LESS THAN (7),
PARTITION p1 VALUES LESS THAN MAXVALUE);
INSERT INTO t1_will_crash VALUES (1), (2), (3), (4), (5), (6), (7), (8), (9), (10), (11);
SELECT * FROM t1_will_crash;
a
1
2
3
4
5
6
7
8
9
10
11
FLUSH TABLES;
# test with CHECK/REPAIR TABLE
# replacing t1_will_crash#P#p1#SP#p1sp0.MYI with a corrupt + unclosed one
CHECK TABLE t1_will_crash;
Table Op Msg_type Msg_text
test.t1_will_crash check warning 1 client is using or hasn't closed the table properly
test.t1_will_crash check error Size of indexfile is: 1024 Should be: 2048
test.t1_will_crash check warning Size of datafile is: 14 Should be: 7
test.t1_will_crash check error Subpartition p1sp0 returned error
test.t1_will_crash check error Corrupt
REPAIR TABLE t1_will_crash;
Table Op Msg_type Msg_text
test.t1_will_crash repair warning Number of rows changed from 1 to 2
test.t1_will_crash repair status OK
SELECT * FROM t1_will_crash;
a
1
2
3
4
5
6
7
8
9
10
11
FLUSH TABLES;
# test with ALTER TABLE ... CHECK/REPAIR PARTITION
# replacing t1_will_crash#P#p1#SP#p1sp0.MYI with a corrupt + unclosed one
ALTER TABLE t1_will_crash CHECK PARTITION p0;
Table Op Msg_type Msg_text
test.t1_will_crash check status OK
ALTER TABLE t1_will_crash CHECK PARTITION all;
Table Op Msg_type Msg_text
test.t1_will_crash check warning 1 client is using or hasn't closed the table properly
test.t1_will_crash check error Size of indexfile is: 1024 Should be: 2048
test.t1_will_crash check warning Size of datafile is: 14 Should be: 7
test.t1_will_crash check error Subpartition p1sp0 returned error
test.t1_will_crash check error Corrupt
ALTER TABLE t1_will_crash CHECK PARTITION p1;
Table Op Msg_type Msg_text
test.t1_will_crash check warning Table is marked as crashed
test.t1_will_crash check warning 1 client is using or hasn't closed the table properly
test.t1_will_crash check error Size of indexfile is: 1024 Should be: 2048
test.t1_will_crash check warning Size of datafile is: 14 Should be: 7
test.t1_will_crash check error Subpartition p1sp0 returned error
test.t1_will_crash check error Corrupt
ALTER TABLE t1_will_crash REPAIR PARTITION p0;
Table Op Msg_type Msg_text
test.t1_will_crash repair status OK
ALTER TABLE t1_will_crash REPAIR PARTITION p0, p1;
Table Op Msg_type Msg_text
test.t1_will_crash repair warning Number of rows changed from 1 to 2
test.t1_will_crash repair status OK
SELECT * FROM t1_will_crash;
a
1
2
3
4
5
6
7
8
9
10
11
DROP TABLE t1_will_crash;
# test of check/repair of crashed partitions in variuos states
CREATE TABLE t1_will_crash (
a VARCHAR(255),
b INT,
c LONGTEXT,
PRIMARY KEY (a, b))
ENGINE=MyISAM
PARTITION BY HASH (b)
PARTITIONS 7;
SELECT COUNT(*) FROM t1_will_crash;
COUNT(*)
33
SELECT (b % 7) AS `partition`, COUNT(*) AS rows_cnt FROM t1_will_crash GROUP BY (b % 7);
partition rows_cnt
0 2
1 5
2 5
3 5
4 4
5 4
6 8
SELECT (b % 7) AS `partition`, b, a, length(c) FROM t1_will_crash ORDER BY `partition`, b, a;
partition b a length(c)
0 0 lost 64
0 7 z lost 64
1 1 abc 64
1 8 tuw 64
1 29 kkkkkkkkKkk 64
1 71 1 broken when head -c1024 on datafile 1024
1 71 eee 64
2 2 def 64
2 9 vxy 64
2 23 lll 64
2 30 2 crashed after _mi_mark_changed 64
2 79 ccc 64
3 3 ghi 64
3 10 aaa 64
3 17 nnn 64
3 24 3 crashed after write_record 64
3 73 ddd 64
4 4 pqr 64
4 11 bbb 64
4 18 4 crashed after flush_cached_blocks 64
4 67 fff 64
5 5 mno 64
5 19 mmm 64
5 40 5 still here since crash in next row in multirow insert? 64
5 89 a 64
6 6 jkl 64
6 13 ooo 64
6 27 6 row 7 (crash before completely written to datafile) 128
6 34 6 row 2 64
6 48 6 row 4 64
6 62 6 row 6 64
6 83 64
6 97 zzzzzZzzzzz 64
FLUSH TABLES;
# truncating p0 to simulate an empty datafile (not recovered!)
# replacing p1 with only the first 1024 bytes (not recovered!)
# replacing p3 with a crashed one at the last row in first insert
# (crashed right after *share->write_record())
# replacing p6 with a crashed MYD file (1) (splitted dynamic record)
ANALYZE TABLE t1_will_crash;
Table Op Msg_type Msg_text
test.t1_will_crash analyze Warning Engine-independent statistics are not collected for column 'c'
test.t1_will_crash analyze status Operation failed
OPTIMIZE TABLE t1_will_crash;
Table Op Msg_type Msg_text
test.t1_will_crash optimize info Found row block followed by deleted block
test.t1_will_crash optimize warning Number of rows changed from 8 to 7
test.t1_will_crash optimize status OK
CHECK TABLE t1_will_crash;
Table Op Msg_type Msg_text
test.t1_will_crash check error Size of datafile is: 0 Should be: 164
test.t1_will_crash check error Partition p0 returned error
test.t1_will_crash check error Corrupt
REPAIR TABLE t1_will_crash;
Table Op Msg_type Msg_text
test.t1_will_crash repair warning Number of rows changed from 2 to 0
test.t1_will_crash repair info Found block that points outside data file at 344
test.t1_will_crash repair warning Number of rows changed from 5 to 4
test.t1_will_crash repair warning Number of rows changed from 0 to 5
test.t1_will_crash repair status OK
SELECT COUNT(*) FROM t1_will_crash;
COUNT(*)
29
SELECT (b % 7) AS `partition`, COUNT(*) AS rows_cnt FROM t1_will_crash GROUP BY (b % 7);
partition rows_cnt
1 4
2 5
3 5
4 4
5 4
6 7
SELECT (b % 7) AS `partition`, b, a, length(c) FROM t1_will_crash ORDER BY `partition`, b, a;
partition b a length(c)
1 1 abc 64
1 8 tuw 64
1 29 kkkkkkkkKkk 64
1 71 eee 64
2 2 def 64
2 9 vxy 64
2 23 lll 64
2 30 2 crashed after _mi_mark_changed 64
2 79 ccc 64
3 3 ghi 64
3 10 aaa 64
3 17 nnn 64
3 24 3 crashed after write_record 64
3 73 ddd 64
4 4 pqr 64
4 11 bbb 64
4 18 4 crashed after flush_cached_blocks 64
4 67 fff 64
5 5 mno 64
5 19 mmm 64
5 40 5 still here since crash in next row in multirow insert? 64
5 89 a 64
6 6 jkl 64
6 13 ooo 64
6 34 6 row 2 64
6 48 6 row 4 64
6 62 6 row 6 64
6 83 64
6 97 zzzzzZzzzzz 64
FLUSH TABLES;
#
# replacing p2 with crashed files (after _mi_mark_changed)
ALTER TABLE t1_will_crash CHECK PARTITION p2;
Table Op Msg_type Msg_text
test.t1_will_crash check warning 1 client is using or hasn't closed the table properly
test.t1_will_crash check status OK
# crash was when index only marked as opened, no real corruption
ALTER TABLE t1_will_crash CHECK PARTITION p2;
Table Op Msg_type Msg_text
test.t1_will_crash check status OK
FLUSH TABLES;
#
# replacing p4 with updated but not closed index file
ALTER TABLE t1_will_crash OPTIMIZE PARTITION p4;
Table Op Msg_type Msg_text
test.t1_will_crash optimize error Found key at page 2048 that points to record outside datafile
test.t1_will_crash optimize error Partition p4 returned error
test.t1_will_crash optimize status Operation failed
ALTER TABLE t1_will_crash CHECK PARTITION p4;
Table Op Msg_type Msg_text
test.t1_will_crash check warning Table is marked as crashed and last repair failed
test.t1_will_crash check warning 1 client is using or hasn't closed the table properly
test.t1_will_crash check warning Size of datafile is: 368 Should be: 252
test.t1_will_crash check error Found 4 keys of 3
test.t1_will_crash check error Partition p4 returned error
test.t1_will_crash check error Corrupt
ALTER TABLE t1_will_crash REPAIR PARTITION p4;
Table Op Msg_type Msg_text
test.t1_will_crash repair warning Number of rows changed from 3 to 4
test.t1_will_crash repair status OK
FLUSH TABLES;
#
# replacing p6 with a crashed MYD file (2) (splitted dynamic record)
ALTER TABLE t1_will_crash CHECK PARTITION p6;
Table Op Msg_type Msg_text
test.t1_will_crash check warning Size of datafile is: 868 Should be: 604
test.t1_will_crash check error Unexpected byte: 0 at link: 340
test.t1_will_crash check error Partition p6 returned error
test.t1_will_crash check error Corrupt
ALTER TABLE t1_will_crash REPAIR PARTITION p6;
Table Op Msg_type Msg_text
test.t1_will_crash repair info Delete link points outside datafile at 340
test.t1_will_crash repair info Delete link points outside datafile at 340
test.t1_will_crash repair status OK
SELECT (b % 7) AS `partition`, b, a, length(c) FROM t1_will_crash
WHERE (b % 7) = 6
ORDER BY `partition`, b, a;
partition b a length(c)
6 6 jkl 64
6 13 ooo 64
6 34 6 row 2 64
6 48 6 row 4 64
6 62 6 row 6 64
6 83 64
6 97 zzzzzZzzzzz 64
FLUSH TABLES;
#
# replacing p6 with a crashed MYD file (3) (splitted dynamic record)
# Different results from the corrupt table, which can lead to dropping
# of the not completely written rows when using REBUILD on a corrupt
# table, depending if one reads via index or direct on datafile.
# Since crash when reuse of deleted row space, CHECK MEDIUM or EXTENDED
# is required (MEDIUM is default) to verify correct behavior!
SELECT (b % 7) AS `partition`, b, a, length(c) FROM t1_will_crash
WHERE (b % 7) = 6
ORDER BY `partition`, b, a;
partition b a length(c)
6 6 jkl 64
6 13 ooo 64
6 34 6 row 2 64
6 83 64
6 97 zzzzzZzzzzz 64
SET @save_optimizer_switch= @@optimizer_switch;
SET @@optimizer_switch='derived_merge=off';
SELECT (b % 7) AS `partition`, b, a FROM (SELECT b,a FROM t1_will_crash) q
WHERE (b % 7) = 6
ORDER BY `partition`, b, a;
partition b a
6 6 jkl
6 13 ooo
6 34 6 row 2
6 48 6 row 4
6 62 6 row 6
6 83
6 97 zzzzzZzzzzz
SET @@optimizer_switch=@save_optimizer_switch;
ALTER TABLE t1_will_crash CHECK PARTITION p6;
Table Op Msg_type Msg_text
test.t1_will_crash check warning Size of datafile is: 868 Should be: 604
test.t1_will_crash check error Record-count is not ok; is 8 Should be: 7
test.t1_will_crash check warning Found 10 key parts. Should be: 7
test.t1_will_crash check error Partition p6 returned error
test.t1_will_crash check error Corrupt
ALTER TABLE t1_will_crash REPAIR PARTITION p6;
Table Op Msg_type Msg_text
test.t1_will_crash repair warning Number of rows changed from 7 to 8
test.t1_will_crash repair status OK
SELECT COUNT(*) FROM t1_will_crash;
COUNT(*)
29
SELECT (b % 7) AS `partition`, COUNT(*) AS rows_cnt FROM t1_will_crash GROUP BY (b % 7);
partition rows_cnt
1 4
2 4
3 5
4 4
5 4
6 8
SELECT (b % 7) AS `partition`, b, a, length(c) FROM t1_will_crash ORDER BY `partition`, b, a;
partition b a length(c)
1 1 abc 64
1 8 tuw 64
1 29 kkkkkkkkKkk 64
1 71 eee 64
2 2 def 64
2 9 vxy 64
2 23 lll 64
2 79 ccc 64
3 3 ghi 64
3 10 aaa 64
3 17 nnn 64
3 24 3 crashed after write_record 64
3 73 ddd 64
4 4 pqr 64
4 11 bbb 64
4 18 4 crashed after flush_cached_blocks 64
4 67 fff 64
5 5 mno 64
5 19 mmm 64
5 40 5 still here since crash in next row in multirow insert? 64
5 89 a 64
6 6 jkl 64
6 13 ooo 64
6 27 6 row 7 (crash before completely written to datafile) 128
6 34 6 row 2 64
6 48 6 row 4 64
6 62 6 row 6 64
6 83 64
6 97 zzzzzZzzzzz 64
ALTER TABLE t1_will_crash CHECK PARTITION all EXTENDED;
Table Op Msg_type Msg_text
test.t1_will_crash check status OK
DROP TABLE t1_will_crash;
|
