sql - 内连接 PostgreSQL

Question

我正在尝试将两个表与此查询连接在一起

select comments.* ,username, title
from comments INNER JOIN users ON comments.user_id = users.user_id 
INNER JOIN posts ON comments.post_id = posts.post_id;

返回的结果是column reference "username" is ambiguous

标签： sqlpostgresql

Answer 1

列应该是形式table.column

选择评论。*，用户名，标题

应该

select comments.* ,YOUR_TABLE.username, YOUR_TABLE.title