sql 多條件查詢的一種簡單的方法
以後我們做多條件查詢,一種是排列結合,另一種是動態拼接SQL
如:我們要有兩個條件,一個日期@addDate,一個是@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,通過exec來執行，我就不寫，
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。
