mySQL 连接同一个表两次 [英] mySQL join same table twice

问题描述

我正在尝试:

select 
audit_log_entries.created_at,
audit_log_orig_term_types.name as originator,
audit_log_orig_term_types.name as terminator
from audit_log_entries 
join audit_log_orig_term_types on audit_log_entries.originator_type_id = audit_log_orig_term_types.id
join audit_log_orig_term_types on audit_log_entries.terminator_type_id = audit_log_orig_term_types.id;

我认为意图很明确，我想要发起者和终结者的两个名字.我在第一个表中有他们的 ID，在另一个表中有他们的名字.

I think the intent is clear, I want both names for the originator and terminator. I have their IDs in the first table and the names on the other table.

我由此得到一个错误:ERROR 1066 (42000): Not unique table/alias: 'audit_log_orig_term_types'

语法错误在哪里?

推荐答案

你可以这样:

select 
 audit_log_entries.created_at,
 audit1.name as originator,
 audit2.name as terminator
from audit_log_entries 
 join audit_log_orig_term_types audit1 on audit_log_entries.originator_type_id = audit1.id
 join audit_log_orig_term_types audit2 on audit_log_entries.terminator_type_id = audit2.id;

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