Query to get data from table 2 if table 1 doesn't have data for some of the column's

SELECT CDAN8 BillTo,CDWMNC CreditCardName, CDWSV CreditCardNumber,CDMNTH CreditCardMonth, CDBLYR CreditCardYear,
 (Case WHEN CDADD1 IS NULL OR CDADD1 = '' THEN ALADD1 ELSE CDADD1 END) CreditCardAddressLine1,(Case WHEN CDMSCY IS NULL OR CDMSCY =

'' THEN ALCTY1 ELSE CDMSCY END) CreditCardCity, (Case WHEN CDUSEX IS NULL OR CDUSEX = '' THEN ALADDS ELSE CDUSEX END)

CreditCardState,
 (Case WHEN CDZIP IS NULL OR CDZIP = '' THEN ALADDZ ELSE CDZIP END)  CreditCardZip,(Case WHEN CDDC IS NULL OR CDDC = '' THEN ALCTR

ELSE CDDC END)  CreditCardCountry,
CDYN03 IsActive  from table1 A LEFT JOIN table2 B ON A.CDAN8 = B.ALAN8
where cdan8='107189' and ((CDBLYR = 2015 and CDMNTH > 8) or CDBLYR >= 2016)
order by cdan8 desc