SQL case用法 CASE 函数将某个表达式与一组简单表达式进行比较以确定结果。例如selectName,( CASE Sex WHEN '0' then '男' WHEN '1' then '女' ELSE 'Unknown' END ) as Sex,IdentificationCard,convert(nvarchar(10),BirthDate,120) as BirthDatefromPersoninfo