query correction for SAP BUSINESS ONE HANA

Dear all,

declare @string nvarchar(255) = '';

declare @fdate DATE = ''

declare @tdate DATE = ''

select sum("DocTotal") from OINV where OINV."CardCode" like '%'+ 'CFA0001' +'%'

and cast(@fdate as 'date')

between cast(@fdate as 'date') and cast(@tdate as 'date')

Help me on query for SAP Business One HANA

Regards,

Nikunj