在sql中进行模式匹配，该怎么办？

Question

so far i have looked up for all relevant info regarding pattern matching in sql but nothing helped me, i am receiving a Code in sms like "yyyy/mm-digit" (digit increments with every message). so i want to ensure that the code sent by user is exactly in that format otherwise another action. So how ?

Here is my old code to check for just numeric code but it want it for eg "2014/08-digit" kinda pattern , how ? (it changes with respect to year and month)

ALTER TRIGGER [dbo].[T_InsertAfterRcvdMessage]
ON
[dbo].[ReceivedMessages]
AFTER INSERT
AS
   Declare @msg as varchar(20)
   Declare @inmbl as varchar(20)
   Declare @cid as int
   Declare @ComplainantId as int

   BEGIN TRY

           SELECT @msg = [Message], @inmbl = FromMobileNo FROM inserted 
             Set @cid = ISNUMERIC(@msg)
              if (@cid = 1)  -- it means @msg is numeric value
                  BEGIN
                    Declare @sts as varchar(50)
                    Declare @mbl as varchar(20)

                     (SELECT @sts = Status, @mbl = ContactNo, @ComplainantId = ComplainantID FROM CPOCMS.dbo.View_ComplaintStatusInfo WHERE ComplaintID = @msg)
                       Exec CmsSMSDb.dbo.ADD_SMS_InQueue @mbl,@sts,0,0,2,1,0,null,@ComplainantId
                  END
              --else
                 -- BEGIN   
                     -- Exec CmsSMSDb.dbo.ADD_SMS_InQueue @inmbl,'Please Provide Valid Complaint No'                        
                 -- END

    END TRY
    BEGIN CATCH
    END CATCH

Answer 1

If you are trying to match "2014/08-", you can use regular expressions or SQL Server built in patterns. With the built in patterns, you would look for:

where code like '2014/08-[0-9]%' and
      code not like '2014/08-%[^0-9]%'

That is, the code starts with 2014/08- and at least one digit. And, it has no non-digit after the hyphen.

EDIT:

In the context of the code:

SELECT @msg = [Message], @inmbl = FromMobileNo FROM inserted;

IF (@msg like '2014/08-[0-9]%' and
    @msg not like '2014/08-%[^0-9]%'
   ) BEGIN
    . . .
END;

EDIT II:

You don't mention that 2014/08 changes, but this is easy enough to handle, sort of (SQL Server could have simpler string and date functions). Try this:

SELECT @msg = [Message], @inmbl = FromMobileNo FROM inserted;

DECLARE @yyyymm varchar(255) = (cast(year(getdate()) as varchar(255)) + '/' +
                                right('00' + cast(month(getdate()) as varchar(255)), 2)
                               );

IF (@msg like @yyyymm + '-[0-9]%' and
    @msg not like @yyyymm + '-%[^0-9]%'
   ) BEGIN
    . . .
END;

This uses the current date for the comparison. You might have another date you want to use.