1问用外连接
左连接例子参考:
var LeftJoin = from emp in ListOfEmployees
join dept in ListOfDepartment on emp.DeptID equals dept.ID into JoinedEmpDept
from dept in JoinedEmpDept.DefaultIfEmpty()
select new
{
EmployeeName = emp.Name,
DepartmentName = dept != null ? dept.Name : null
}; 2问用内连接
from a in team1
join b in team2 on new{a.name,a.score } equals new{b.name ,b.score}
.....
左连接例子参考:
var LeftJoin = from emp in ListOfEmployees
join dept in ListOfDepartment on emp.DeptID equals dept.ID into JoinedEmpDept
from dept in JoinedEmpDept.DefaultIfEmpty()
select new
{
EmployeeName = emp.Name,
DepartmentName = dept != null ? dept.Name : null
}; 2问用内连接
from a in team1
join b in team2 on new{a.name,a.score } equals new{b.name ,b.score}
.....
解决方案 »
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