删除查询＆＃34; ERROR 2006（HY000）：MySQL服务器已经消失了＃34;

Question

要点：

我在P - 表中有250个miljon行，在J - 表中有100 000行。我正在尝试删除P - 表中与J - 表缺乏关系的所有行。

预期结果：

每一行缺少关系（约100 000有关系）将从P - 表中删除。

我正在使用的查询：

DELETE P 
FROM P 
LEFT JOIN J ON J.P_id = P.id 
WHERE J.id IS NULL;

我收到的错误：

ERROR 2006 (HY000): MySQL server has gone away

我尝试了什么：

SET innodb_lock_wait_timeout=63000;
SET wait_timeout=63000;

/* ... followed by the query stated above ... */

---

问题

如何达到预期效果？

---

修改

其他信息 - 进程列表

所以我猜这个查询仍在运行..

+-----+------+-----------+---------+---------+-------+--------------+------------------------------------------------------------------------------------------------------+
| Id  | User | Host      | db      | Command | Time  | State        | Info                                                                                                 |
+-----+------+-----------+---------+---------+-------+--------------+------------------------------------------------------------------------------------------------------+
| 540 | root | localhost | scraper | Query   | 63298 | Sending data | DELETE Domain_Page FROM Domain_Page LEFT JOIN StructuredData_Joppli ON StructuredData_Joppli.Domain_ |
| 556 | root | localhost | scraper | Query   |     0 | NULL         | show processlist                                                                                     |
+-----+------+-----------+---------+---------+-------+--------------+------------------------------------------------------------------------------------------------------+

Answer 1

更改此

 DELETE P
 FROM P

到

 DELETE 
 FROM P

Answer 2

如果没有索引关系，请尝试删除较小的部分。

DELETE P 
FROM P 
LEFT JOIN J ON J.P_id = P.id 
WHERE J.id IS NULL LIMIT 10000;

修改

使用子查询怎么样？请先试用一下测试表。

DELETE p FROM p
JOIN 
(SELECT J.P_Id 
 FROM J LEFT JOIN P ON J.P_Id=P.Id 
 WHERE j.Id IS NULL LIMIT 1000
) P2 ON p.Id=P2.P_Id

Answer 3

delete 
from P left join J ON J.P_id = P.id 
where J.id IS NULL 

如果列不是NULL但只是空白，则需要执行以下操作：

delete 
frome P 
left join J ON J.P_id = P.id 
where J.id=''