Bug #13249921 ASSERT !BPAGE->FILE_PAGE_WAS_FREED, USUALLY IN
TRANSACTION ROLLBACK Description: During the rollback operation, a blob page is removed earlier than desired. Consider following scenario: 1. create table t1(a int primary key,b blob) engine=innodb; 2. insert into t1 values (1,repeat('b',9000)); 3. begin; 4. update t1 set b=concat(b,'b'); 5. update t1 set a=a+1; 6. insert into t1 values (1,repeat('b',9000)); 7. rollback; The update operation in line 5 produces 2 undo log record. The first undo record (TRX_UNDO_DEL_MARK_REC) goes to trx->update_undo and the second undo record (TRX_UNDO_INSERT_REC) goes to trx->insert_undo. During rollback, they are executed out of order. When the undo record TRX_UNDO_DEL_MARK_REC is applied/executed, the blob ownership is also reset. Because of this the blob page is released earlier than desired. This blob page must have been freed only as part of applying/executing the undo record TRX_UNDO_INSERT_REC. This problem can be avoided by executing the undo records in order. This patch will make innodb to execute the undo records in order. rb://1125 approved by Marko.
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