mysql case when

case when

1. 语法

• 简单函数

CASE [col_name] WHEN [value1] THEN [result1]…ELSE [default] END

• 搜索函数

CASE WHEN [expr] THEN [result1]…ELSE [default] END

2. 举例

• 例子

select nType,count(nType) as nCount,case nType when 1 then '图书' when 2 then '听书'when 3 then '视频' when 4 then '期刊' when 5 then '图片' when 6 then '精选' end as sBookType from TbCompanyBooks group by nType

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