使用LIKE运算符和存储过程参数

Question

我有一个存储过程,使用LIKE操作员在一些其他参数中搜索卡车位置

   @location nchar(20),
   @time time,
   @date date
AS
   select 
       DonationsTruck.VechileId, Phone, Location, [Date], [Time]
   from 
       Vechile, DonationsTruck
    where 
       Vechile.VechileId = DonationsTruck.VechileId
       and (((Location like '%'+@location+'%') or (Location like '%'+@location) or (Location like @location+'%') ) or [Date]=@date or [Time] = @time)

我将其他参数置零并仅按位置搜索,但即使我使用该位置的全名,它也始终不返回任何结果

Answer 1

你的数据类型@location nchar(20)应该是@location nvarchar(20),因为nChar有一个固定的长度(用空格填充).
如果Location也是nchar,你将不得不转换它:

 ... Cast(Location as nVarchar(200)) like '%'+@location+'%' ...   

要使用和AND条件启用可空参数,只需使用IsNull或Coalesce进行比较,这在您的示例中不需要使用OR.

例如,如果您想比较位置和日期和时间.

@location nchar(20),
@time time,
@date date
as
select DonationsTruck.VechileId, Phone, Location, [Date], [Time]
from Vechile, DonationsTruck
where Vechile.VechileId = DonationsTruck.VechileId
and (((Location like '%'+IsNull(@location,Location)+'%')) and [Date]=IsNUll(@date,date) and [Time] = IsNull(@time,Time))

Answer 2

我正在做同样的事情。检查下面的声明。为我工作！

SELECT * FROM [Schema].[Table] WHERE [Column] LIKE '%' + @Parameter + '%'