连接 table 时出现单力索引抛出错误

Question

我正在尝试使用左联接桥接两个 table 并强制索引一个仅存在于已联接的 table 上的索引，但出现以下错误：

You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'FORCE INDEX (l.sfdcId) WHERE l.sfdcId = '003A000001eR0HsIAK' ORDER BY a.activity' at line 3

这是查询的输出运行（如果我删除 FORCE INDEX 则工作正常）：

SELECT a.activityDate,a.primaryAttributeValue,a.attributeDescription,l.firstName,l.lastName,l.title,l.email
FROM activities AS a LEFT JOIN
     leads AS l 
     ON a.leadId = l.leadId FORCE INDEX (l.sfdcId) 
WHERE l.sfdcId = '003A000001eR0HsIAK'
ORDER BY a.activityDate DESC

知道为什么会失败吗？

Answer 1

FORCE INDEX 在 table 定义之后：

SELECT a.activityDate,a.primaryAttributeValue,a.attributeDescription,
       l.firstName,l.lastName,l.title,l .email
FROM activities a LEFT JOIN
     leads l FORCE INDEX (sfdcId)
     ON a.leadId = l.leadId 
WHERE l.sfdcId = '003A000001eR0HsIAK'
ORDER BY a.activityDate DESC ;

连接 table 时出现单力索引抛出错误

Single force index throwing error on joined table

php

mysql

mysql-error-1064