日期不能在将来的SQL中

Question

I'm trying to add a kind of constraint that will prevent the user from entering dates in the future, I need it to raise an error when the user tries to do so.

This is what I have so far:

Create Procedure CustomerBooks (@month int, @year int)
AS
BEGIN
    SELECT     
       SaleNumber, 
       month(saledate) as SaleMonth, year(saledate) as SaleYear,
       CustomerNumber, EmployeeNumber, SubTotal, GST, Total
    FROM         
       sale
    Where  
       month(saledate) = @month 
       and YEAR (saledate) = @year 
End

If salemonth > GETDATE(Month(saledate))  
   or saleyear > GETDATE(YEAR(saledate))
begin
   Raiserror ('Invalid entry, you cannot enter future dates',16,1)
end


EXEC dbo.CustomerBooks @month = '1', @year = '2012'

Answer 1

If you are using SQL Server, the simplest solution would be to add a CHECK CONSTRAINT to prevent anyone entering a date beyond the (SQL Server) system date.

ALTER TABLE Sale ADD CONSTRAINT CKC_SALE_SALEDATE CHECK (SaleDate <= GetDate());

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Edit 1 Regarding OP's comment on adding a check constraint to a stored procedure

The benefit of a CHECK CONSTRAINT is that it can't be bypassed without disabling it.

There will always be instances where someone inserts/updates the data without going through the stored procedure you've set up. The constraint will prevent entering incorrect data.

---

Edit 2 Regarding OP's error when checking on GetDate()

The following construct currently doesn't compile

   If salemonth > GETDATE(Month(saledate))  
   or saleyear > GETDATE(YEAR(saledate))

The error message hints to what is in error here, the GetDate() function doesn't take any parameters. Most likely, I suspect you meant to write something like this

   If salemonth > MONTH(GetDate())  
   or saleyear > YEAR(GetDate())

---

Edit 3

Verify that the inputs are not in the future could be done by using following if/then/else construct. Another option would be to convert the inputs to an actual date and check on that.

IF (YEAR(GetDate()) < @year)    
  Raiserror ('Invalid entry, you cannot enter future dates',16,1)
ELSE IF (YEAR(GetDate()) = @year) AND (MONTH(GetDate()) < @month) 
  Raiserror ('Invalid entry, you cannot enter future dates',16,1)

SQL Fiddle Example

Answer 2

Use a trigger Instead.

Create or replace trigger tri_name
before insert on  sale 
begin
If salemonth > GETDATE(Month(saledate)) or saleyear > GETDATE(YEAR(saledate))
then 
Raiserror ('Invalid entry, you cannot enter future dates',16,1)
end;
/

May be this will help You.