MySQL加入和删除只发生第一次发生

Question

我必须从MySQL表中删除40 mln行。

我必须找到与输出的所有行 - >“静态输出” 然后删除上面的输出行和删除其上面的输出和比其他产值“的同一台主机 和服务的下一行STATIC OUTPUT“。

的样本数据：

列- > ID，主机，服务，输出

1,"127.0.0.1","service1","STATIC OUTPUT" 
2,"127.0.0.2","service5","RANDOM OUTPUT X0" 
3,"127.0.0.2","service5","STATIC OUTPUT" 
4,"127.0.0.3","service1","RANDOM OUTPUT X1" 
5,"127.0.0.3","service10","RANDOM OUTPUT X2" 
6,"127.0.0.2","service5","RANDOM OUTPUT X3" 
7,"127.0.0.1","service2","RANDOM OUTPUT X4" 
8,"127.0.0.1","service1","RANDOM OUTPUT X5" 
9,"127.0.0.2","service4","RANDOM OUTPUT X6" 
10,"127.0.0.3","service10","RANDOM OUTPUT X7" 
11,"127.0.0.1","service1","RANDOM OUTPUT X7" 
12,"127.0.0.1","service1","RANDOM OUTPUT X8" 
13,"127.0.0.1","service1","RANDOM OUTPUT X9" 
14,"127.0.0.2","service5","RANDOM OUTPUT X10" 
15,"127.0.0.1","service1","STATIC OUTPUT" 
16,"127.0.0.1","service1","RANDOM OUTPUT X11" 
17,"127.0.0.1","service1","RANDOM OUTPUT X12"  
... 

例子：当我们发现

1,"127.0.0.1","service1","STATIC OUTPUT" 

我们应该删除ID为值的行1和8，

8,"127.0.0.1","service1","RANDOM OUTPUT X5" 

当我们发现

3,"127.0.0.2","service5","STATIC OUTPUT" 

我们应该删除与ID值3和6行，

6,"127.0.0.2","service5","RANDOM OUTPUT X3" 

我写了这样的事情（选择，因为测试查询的DELETE语句的这一翻译），

SELECT * FROM data r1 INNER JOIN (SELECT id, host, service 
FROM data 
WHERE output = 'STATIC OUTPUT') r2 ON 
     r1.id>r2.id AND r1.service=r2.service 
     AND r1.host=r2.host 
     AND r1.output<>'STATIC OUTPUT' 
GROUP BY r1.host, r1.service 

但我认为这是一种错误的方式。

MySQL 5.1.73

Answer 1

校正

现在，这应该这样做！：

SELECT min(sp.id) as id FROM 
(SELECT hs.id, hs.host, hs.service, hs.output, so.id as soid 
FROM data hs 
INNER JOIN 
(SELECT id,host,service,output FROM data 
WHERE output = "STATIC OUTPUT") so 
ON so.host = hs.host and so.service = hs.service 
AND hs.id > so.id WHERE hs.output <> "STATIC OUTPUT") sp 
group by host,service, soid 
UNION 
SELECT id FROM data WHERE output = "STATIC OUTPUT"; 

Answer 2

您可以使用LIMIT语句选择第一个匹配项。 https://dev.mysql.com/doc/refman/5.7/en/select.html

SELECT * FROM data LIMIT 1;

编辑：

此示例会发现你的ID来擦除

 
    CREATE OR REPLACE VIEW v AS 
    SELECT r1.id as id1 , r2.id as id2 FROM data r1 
    INNER JOIN data r2 ON r1.host=r2.host AND r1.service = r2.service 
    WHERE LOWER(r1.output) LIKE "static output" AND r1.id < r2.id; 

 
    SELECT DISTINCT id1 FROM v 
    UNION 
    SELECT DISTINCT id2 FROM v; 

输出：

ID：1 3 6 8