-- 1.使用大於0表
show open tables where `database` = 'test' and in_use > 0 ;
-- 2.request_trx_id請求鎖 與 blocking_trx_id產生鎖原因
select * from information_schema.innodb_lock_waits;
select trx_id,trx_mysql_thread_id from information_schema.innodb_trx ;
-- 3.被鎖語句id
select
now(),
(unix_timestamp(now()) - unix_timestamp(a.trx_started)
) diff_sec,
b.id,-- 被鎖語句id
b.user,
b.host,
b.db,
c.lock_type,
c.lock_table,
c.lock_index
from
information_schema.innodb_trx a
inner join information_schema.processlist b
on a.trx_mysql_thread_id = b.id
inner join information_schema.innodb_locks c
on a.trx_requested_lock_id = c.lock_id ;
-- 4.檢視正在鎖的事務,表名，鎖狀態
select * from information_schema.innodb_locks;
-- 5.檢視id對應的sql
show full processlist;
select b.processlist_id,a.thread_id,a.sql_text from
performance_schema.events_statements_current a, performance_schema.threads b
where a.thread_id=b.thread_id
-- 6.殺掉程序
kill ??
-- 一步到位
select * from sys.`innodb_lock_waits`;
-- 以下語句適用5.6（含有performance_schema.events_statements_current）以上版本
select
b.`trx_mysql_thread_id` 被鎖id,
(select
a.sql_text
from
performance_schema.events_statements_current a,
performance_schema.threads b
where a.thread_id = b.thread_id
and b.processlist_id = b.`trx_mysql_thread_id`) 被鎖sql,
d.`lock_table` 被鎖表,
c.`trx_mysql_thread_id` 鎖表id, -- 殺掉 kill ??
(select
a.sql_text
from
performance_schema.events_statements_current a,
performance_schema.threads b
where a.thread_id = b.thread_id
and b.processlist_id = c.`trx_mysql_thread_id`) 鎖表sql,
e.`lock_table` 鎖表
from
information_schema.innodb_lock_waits a
left join information_schema.innodb_trx b
on a.`requesting_trx_id` = b.`trx_id`
left join information_schema.innodb_trx c
on a.`blocking_trx_id` = c.`trx_id`
left join information_schema.innodb_locks d
on a.`requesting_trx_id` = d.`lock_trx_id`
left join information_schema.innodb_locks e
on a.`blocking_trx_id` = e.`lock_trx_id` ;
--適用於5.7及以上版本
select t2.processlist_id,from_unixtime(unix_timestamp(now())-t4.time) start_time,t1.*,t3.sql_text from
(select
object_schema,object_name,lock_status,owner_thread_id
from
`performance_schema`.metadata_locks
where
owner_thread_id != sys.ps_thread_id (connection_id())
and object_schema='test'
) t1
left join `performance_schema`.threads t2 on t1.owner_thread_id=t2.thread_id
left join performance_schema.events_statements_current t3 on t1.owner_thread_id=t3.thread_id
left join information_schema.`processlist` t4 on t4.id=t2.processlist_id
order by t1.object_name
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