如何从三个不同的表

Question

我有三个表person_firstname，person_middlename，person_lastname。所有表格都有公共字段entity_id。我必须在单个记录中选择员工全名。不确定人只有名字，所有名字或仅姓氏。我试过联合它返回三行。

还需要通过entity_id记录特定员工。所以需要匹配像entity_id = 123这样的记录。其entity_id为123的员工的所有姓名。

Answer 1

SELECT p1.first_name person_firstname，p2.middle_name person_middlename，p3.last_name person_lastname FROM person_firstname p1 JOIN person_middlename p2 ON p1.entity_id = p2.entity_id JOIN person_lastname p3 ON p3.entity_id = p2.entity_id;

Answer 2

a b c d
0 1 1 1
1 0 1 1
1 1 0 1
1 1 1 0
0 0 0 0