SQL CASE WHEN 或 IF ELSE IF

Question

我在一个案例中有多个条件要满足
我想知道我是否可以使用 > < 而不是定义每个案例

在这种情况下，当信用评级小于 3 时，将插入“NO TRADE”一词
大于 3，小于 5 将是“POOR”，依此类推

SELECT  ClientId, 
    FirstName,
    LastName,
    Gender,
    DateOfBirth,
    CreditRating,

        CASE CreditRating

            WHEN 0 THEN 'NO TRADE'
            WHEN 1 THEN 'NO TRADE'
            WHEN 2 THEN 'NO TRADE'
            WHEN 3 THEN 'POOR'
            WHEN 4 THEN 'POOR'
            WHEN 5 THEN 'AVARAGE'
            WHEN 6 THEN 'AVARAGE'
            WHEN 7 THEN 'GOOD'
            ELSE 'PERFECT' 

            END AS RATING

    FROM dbo.client

Answer 1

当然有可能。

CASE 

WHEN CreditRating <= 2  THEN 'NO TRADE'
WHEN CreditRating  <= 4 THEN 'POOR'
WHEN CreditRating  <= 6 THEN 'AVARAGE'
WHEN CreditRating  = 7 THEN 'GOOD'

ELSE 'PERFECT' 

END AS RATING