set names utf8; CREATE TABLE corrupt_bit_test_ā( a INT AUTO_INCREMENT PRIMARY KEY, b CHAR(100), c INT, z INT, INDEX idx(b)) ENGINE=InnoDB STATS_PERSISTENT=0; INSERT INTO corrupt_bit_test_ā VALUES(0,'x',1, 1); CREATE UNIQUE INDEX idxā ON corrupt_bit_test_ā(c, b); CREATE UNIQUE INDEX idxē ON corrupt_bit_test_ā(z, b); SELECT * FROM corrupt_bit_test_ā; a b c z 1 x 1 1 INSERT INTO corrupt_bit_test_ā SELECT 0,b,c+1,z+1 FROM corrupt_bit_test_ā; select count(*) from corrupt_bit_test_ā; count(*) 2 SET @save_dbug = @@SESSION.debug_dbug; SET debug_dbug = '+d,dict_set_index_corrupted'; check table corrupt_bit_test_ā; Table Op Msg_type Msg_text test.corrupt_bit_test_ā check Warning InnoDB: Index idx is marked as corrupted test.corrupt_bit_test_ā check Warning InnoDB: Index idxā is marked as corrupted test.corrupt_bit_test_ā check Warning InnoDB: Index idxē is marked as corrupted test.corrupt_bit_test_ā check error Corrupt SET @@SESSION.debug_dbug = @save_dbug; CREATE INDEX idx3 ON corrupt_bit_test_ā(b, c); ERROR HY000: Index idx is corrupted CREATE INDEX idx4 ON corrupt_bit_test_ā(b, z); ERROR HY000: Index idx is corrupted select c from corrupt_bit_test_ā; ERROR HY000: Index corrupt_bit_test_ā is corrupted select z from corrupt_bit_test_ā; ERROR HY000: Index corrupt_bit_test_ā is corrupted show warnings; Level Code Message Warning 180 InnoDB: Index idxē for table `test`.`corrupt_bit_test_ā` is marked as corrupted Error 1712 Index corrupt_bit_test_ā is corrupted insert into corrupt_bit_test_ā values (10001, "a", 20001, 20001); select * from corrupt_bit_test_ā use index(primary) where a = 10001; a b c z 10001 a 20001 20001 begin; insert into corrupt_bit_test_ā values (10002, "a", 20002, 20002); delete from corrupt_bit_test_ā where a = 10001; insert into corrupt_bit_test_ā values (10001, "a", 20001, 20001); rollback; drop index idxā on corrupt_bit_test_ā; check table corrupt_bit_test_ā; Table Op Msg_type Msg_text test.corrupt_bit_test_ā check Warning InnoDB: Index idx is marked as corrupted test.corrupt_bit_test_ā check Warning InnoDB: Index idxē is marked as corrupted test.corrupt_bit_test_ā check error Corrupt set names utf8; select z from corrupt_bit_test_ā; ERROR HY000: Index corrupt_bit_test_ā is corrupted drop index idxē on corrupt_bit_test_ā; CREATE INDEX idx3 ON corrupt_bit_test_ā(b, c); ERROR HY000: Index idx is corrupted CREATE INDEX idx4 ON corrupt_bit_test_ā(b, z); ERROR HY000: Index idx is corrupted drop index idx on corrupt_bit_test_ā; CREATE INDEX idx3 ON corrupt_bit_test_ā(b, c); CREATE INDEX idx4 ON corrupt_bit_test_ā(b, z); select z from corrupt_bit_test_ā limit 10; z 20001 1 2 drop table corrupt_bit_test_ā;