MySQL死锁导致无法查询
最近在维护数据库时,解析数据时候,数据一直不能入库。原因知道,是因为MySQL的事务产生了死锁,前几次我直接重启MySQL。
最近在维护数据库时,解析数据时候,数据一直不能入库。原因知道,是因为MySQL的事务产生了死锁,前几次我直接重启MySQL。
最近发现频繁的出现。所以找到一种方法。
SELECT * FROM INFORMATION_SCHEMA.INNODB_TRX;
trx_id trx_state trx_started trx_requested_lock_id trx_wait_started trx_weight trx_mysql_thread_id trx_query trx_operation_state trx_tables_in_use trx_tables_locked trx_lock_structs trx_lock_memory_bytes trx_rows_locked trx_rows_modified trx_concurrency_tickets trx_isolation_level trx_unique_checks trx_foreign_key_checks trx_last_foreign_key_error trx_adaptive_hash_latched trx_adaptive_hash_timeouttrx_id trx_state trx_started trx_requested_lock_id trx_wait_started trx_weight trx_mysql_thread_id trx_query trx_operation_state trx_tables_in_use trx_tables_locked trx_lock_structs trx_lock_memory_bytes trx_rows_locked trx_rows_modified trx_concurrency_tickets trx_isolation_level trx_unique_checks trx_foreign_key_checks trx_last_foreign_key_error trx_adaptive_hash_latched trx_adaptive_hash_timeout
查看事件比较久的事物。如何当前时间select sysdate();AM 10:07而事物开始的时间是:AM 9:50,,显示是不正常的。根据这个事物的线程ID(trx_mysql_thread_id)。
执行命令:
kill 线程ID
数据库修复正常。
查看正在锁的事务
SELECT * FROM INFORMATION_SCHEMA.INNODB_LOCKS;
查看等待锁的事务
SELECT * FROM INFORMATION_SCHEMA.INNODB_LOCK_WAITS;

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