UFN_SEPAMANDATE_SINGLECONSTITUENTACCOUNT

CREATE function dbo.UFN_SEPAMANDATE_SINGLECONSTITUENTACCOUNT
(
    @ID uniqueidentifier
)
returns bit
with execute as caller
as begin
    if @ID is null
        return 0;

    declare @NUMACCOUNTS int = 0;
    declare @CONSTITUENTACCOUNTID uniqueidentifier = null;
    declare @BATCHREVENUECONSTITUENTACCOUNTID uniqueidentifier = null;
    declare @BATCHSPONSORSHIPCONSTITUENTACCOUNTID uniqueidentifier = null;

    select
        @CONSTITUENTACCOUNTID = SEPAMANDATE.CONSTITUENTACCOUNTID,
        @BATCHREVENUECONSTITUENTACCOUNTID = SEPAMANDATE.BATCHREVENUECONSTITUENTACCOUNTID,
        @BATCHSPONSORSHIPCONSTITUENTACCOUNTID = SEPAMANDATE.BATCHSPONSORSHIPCONSTITUENTACCOUNTID
    from dbo.SEPAMANDATE
    where SEPAMANDATE.ID = @ID;

    if @CONSTITUENTACCOUNTID is not null
        set @NUMACCOUNTS = @NUMACCOUNTS + 1;

    if @BATCHREVENUECONSTITUENTACCOUNTID is not null
        set @NUMACCOUNTS = @NUMACCOUNTS + 1;

    if @BATCHSPONSORSHIPCONSTITUENTACCOUNTID is not null
        set @NUMACCOUNTS = @NUMACCOUNTS + 1;

    return case when @NUMACCOUNTS = 1 then 1 else 0 end;
end