需要此查詢的邏輯？

Question

我是Sql的初學者請指導我。我有兩個1）表tblEmploee & 2）tblAgeGroup

什麼是實現AgeGroupName到tblEmploee表的最佳途徑。

Answer 1

溶液＃1 -

SELECT e.*, a.AgeGroupName 
FROM dbo.tblEmploee e 
JOIN dbo.tblAgeGroup a ON e.EmpAge BETWEEN a.AgeGroupMinAge AND a.AgeGroupMaxAge 

溶液＃2 -

SELECT * 
FROM dbo.tblEmploee e 
OUTER APPLY (
    SELECT TOP 1 a.AgeGroupName 
    FROM dbo.tblAgeGroup a 
    WHERE e.EmpAge BETWEEN a.AgeGroupMinAge AND a.AgeGroupMaxAge 
) a 

溶液＃3 -

SELECT e.*, AgeGroupName = (
    SELECT a.AgeGroupName 
    FROM dbo.tblAgeGroup a 
    WHERE e.EmpAge BETWEEN a.AgeGroupMinAge AND a.AgeGroupMaxAge 
) 
FROM dbo.tblEmploee e