Microsoft SQL Server（T-SQL）

在选择中，使用：

select case when Obsolete = 'N' or InStock = 'Y' then 'YES' else 'NO' end

在where子句中，使用：

where 1 = case when Obsolete = 'N' or InStock = 'Y' then 1 else 0 end

SELECT  
(CASE 
     WHEN (Obsolete = 'N' OR InStock = 'Y') THEN 'YES'
                                            ELSE 'NO' 
 END) as Salable
, * 
FROM Product

SELECT
if((obsolete = 'N' OR instock = 'Y'), 1, 0) AS saleable, *
FROM
product;

使用CASE。像这样。

SELECT Salable =
        CASE Obsolete
        WHEN 'N' THEN 1
        ELSE 0
    END

如果您是第一次将结果插入表中，而不是将结果从一个表传输到另一个表，这在Oracle 11.2g中适用：

INSERT INTO customers (last_name, first_name, city)
    SELECT 'Doe', 'John', 'Chicago' FROM dual
    WHERE NOT EXISTS
        (SELECT '1' from customers
            where last_name = 'Doe'
            and first_name = 'John'
            and city = 'Chicago');

SELECT CASE WHEN Obsolete = 'N' or InStock = 'Y' THEN 1 ELSE 0 
             END AS Saleable, * 
FROM Product