sql 多条件查询的一种简单的方法
以後我們做多條件查詢,一种是排列结合,另一种是动态拼接SQL
如:我们要有两个条件,一个日期@addDate,一个是@name
第一種寫法是
if (@addDate is not null) and (@name <> "")
select * from table where addDate = @addDate and name = @name
else if (@addDate is not null) and (@name ="")
select * from table where addDate = @addDate
else if(@addDate is null) and (@name <> "")
select * from table where and name = @name
else if(@addDate is null) and (@name = "")
select * from table
第二種就是動態組成SQL,通过exec来执行,我就不写,
昨天我想到一種辦法
select * from table where (addDate = @addDate or @addDate is null) and (name = @name or @name = "")
結果一調試,成功。