USP_CREDITCARD_TOKENEXISTSANDNUMBERMATCHES

create procedure dbo.USP_CREDITCARD_TOKENEXISTSANDNUMBERMATCHES
(
    @CREDITCARDTOKEN uniqueidentifier,
    @PARTIALCARDNUMBER nvarchar(4),
    @TOKENEXISTS bit output,
    @NUMBERMATCHES bit output
)
as
begin
    set @TOKENEXISTS = 0;
    set @NUMBERMATCHES = 0;
    declare @PARTIAL nvarchar(4);

    if @CREDITCARDTOKEN is not null and @CREDITCARDTOKEN <> N'00000000-0000-0000-0000-000000000000' and len(@PARTIALCARDNUMBER) > 0
    begin
        select
            @TOKENEXISTS = 1,
            @PARTIAL = CREDITCARD.CREDITCARDPARTIALNUMBER
        from 
            dbo.CREDITCARD 
        where 
            CREDITCARD.CREDITCARDTOKEN = @CREDITCARDTOKEN;

        if @TOKENEXISTS = 1  and @PARTIALCARDNUMBER = coalesce(@PARTIAL, N'')
        begin
            set @NUMBERMATCHES = 1;
        end
    end
end