用于搜索数据库的where子句中的SQL if语句

我正在创建一个存储过程来返回搜索结果,其中一些参数是可选的.

我想在where子句中使用"if语句",但无法使其正常工作.在那里条款应仅由非空的参数进行过滤.

这是sp

ALTER PROCEDURE spVillaGet 
-- Add the parameters for the stored procedure here
@accomodationFK int = null,
@regionFK int = null,
@arrivalDate datetime,
@numberOfNights int,
@sleeps int = null,
@priceFloor money = null,
@priceCeil money = null
AS
BEGIN
-- SET NOCOUNT ON added to prevent extra result sets from
-- interfering with SELECT statements.
SET NOCOUNT ON;

-- Insert statements for procedure here
select tblVillas.*, tblWeeklyPrices.price from tblVillas
INNER JOIN tblWeeklyPrices on tblVillas.villaId = tblWeeklyPrices.villaFK
where 
    If @accomodationFK <> null then
        accomodationTypeFK = @accomodationFK 
     @regionFK <> null Then
        And regionFK = @regionFK 
    IF @sleeps <> null Then
        And sleeps = @sleeps 
    IF @priceFloor <> null Then
        And price >= @priceFloor And price <= @priceCeil


END

任何想法如何做到这一点？

1> Ovidiu Pacur..：

---

select tblVillas.*, tblWeeklyPrices.price 
from tblVillas
INNER JOIN tblWeeklyPrices on tblVillas.villaId = tblWeeklyPrices.villaFK
where (@accomodationFK IS null OR accomodationTypeFK = @accomodationFK)
  AND (@regionFK IS null or regionFK = @regionFK)
  AND (@sleeps IS null OR sleeps = @sleeps)
  AND (@priceFloor IS null OR (price BETWEEN @priceFloor And @priceCeil))

---

为什么会这样:如果@var为null,则整行都为true,无论该行的其余部分如何(因此被忽略和未经过滤).如果它不为null,则该行为false*除非*ColVar = @ var,因此应用过滤器.我第一次阅读这种过滤器样式时感到困惑,但现在到处都使用它.