Question

任何人都可以告诉我这个查询的错误错误：ER_PARSE_ERROR：你的SQL语法有错误;查看与您的MySQL服务器版本对应的手册，以便在第1行的YEAR附近使用正确的语法

SELECT uw.user_id, cd.LEW, cd.event_date,dd.hwRate,d3.Wdata
FROM user_worker AS uw
LEFT JOIN _device1 AS cd ON uw.user_id = cd.uuid     
WHERE YEAR(cd.event_date)=2018 
LEFT JOIN _device2 AS dd ON uw.user_id = dd.uuid 
WHERE YEAR(dd.event_date)=2018 
LEFT JOIN _device3 AS d3 ON uw.user_id = d3.uuid 
WHERE YEAR(d3.event_date)=2018

Answer 1

正如评论中所说，你不能在每个联接中有多个位置，但是如果用＆＃34; AND＆＃34;替换所有位置，它将起作用：

SELECT uw.user_id, cd.LEW, cd.event_date,dd.hwRate,d3.Wdata
FROM user_worker AS uw
LEFT JOIN _device1 AS cd ON uw.user_id = cd.uuid     
 AND YEAR(cd.event_date)=2018 
LEFT JOIN _device2 AS dd ON uw.user_id = dd.uuid 
 AND YEAR(dd.event_date)=2018 
LEFT JOIN _device3 AS d3 ON uw.user_id = d3.uuid 
 AND  YEAR(d3.event_date)=2018

左边用where子句连接三个表

1 个答案: