sql MSSQL左右外连接

Posted 2021-05-13

-- Left Outer Join Sample
SELECT Ps.BusinessEntityID,
       Ps.FirstName,
       Ps.LastName,
       Emp.NationalIDNumber,
       Emp.JobTitle
FROM Person.Person AS Ps
    LEFT OUTER JOIN HumanResources.Employee AS Emp
        ON Ps.BusinessEntityID = Emp.BusinessEntityID;
        
        
-- Right Outer Join Sample
SELECT Ps.BusinessEntityID,
       Ps.FirstName,
       Ps.LastName,
       Emp.NationalIDNumber,
       Emp.JobTitle
FROM Person.Person AS Ps
    RIGHT OUTER JOIN HumanResources.Employee AS Emp
        ON Ps.BusinessEntityID = Emp.BusinessEntityID;