image.png
image.png
var list = (from teacher in teachers
join student in students on teacher.TeacherId equals student.TeacherId into temp
from tt in temp.DefaultIfEmpty()
select new
{
teacherName = teacher.TeacherName,
studentName = tt?.StudentName
}).Dump("查询语句");
image.png
1、Join 1.1定义 1.2结果 2、Left Join 2.1定义 2.2结果
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本文标题：Join & Left Join
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