如何通过 mysql left join 获取名字两次

Question

我有两张桌子。一个用于会员信息，另一个用于董事会信息。我想用名称显示 'writer' 和 'viewer' 但我只能通过 'LEFT JOIN'

显示其中一个

SELECT * FROM `table_a`
idx name    
1   Admin   
2   Superman    
3   Ironman 
4   Batman  


SELECT * FROM `table_bbs`
idx writer  title       viewer  
1   1       Hi All          0   
2   1       hello           2   
3   2       My name is      3   
4   3       Do not click    4   
    



SELECT bbs.writer, a.name, bbs.title, bbs.viewer FROM `table_bbs` AS bbs
    LEFT JOIN table_a AS a ON a.idx = bbs.writer;
writer  name    title           viewer  
1   Admin       Hi All          0   
1   Admin       hello           2   
2   Superman    My name is      3   
3   Ironman     Do not click    4

如何获得查看者的姓名？

Answer 1

如果观众数据来自 table_a

SELECT bbs.writer, a.name as writer_name, bbs.title, bbs.viewer, b.name as viewer_name FROM `table_bbs` AS bbs
    LEFT JOIN table_a AS a ON a.idx = bbs.writer
    LEFT JOIN table_a AS b ON b.idx = bbs.viewer

如何通过 mysql left join 获取名字两次

how to get name twice via mysql left join

mysql

left-join