SQL code question

Good afternoon

I'm trying to create some audit SQL view in Responsys to determine what records are in my contact list (a.) that are are OPTIN and Deliverable but not in another table (b.)

In addition I need to return all the other fields from (a.) for analysis.

I wrote the code below

SELECT a.RIID_, a.EMAIL_ADDRESS_, a.CREATED_DATE_ as MCL_CREATED_DATE

,a.MODIFIED_DATE_

,a.EMAIL_CAPTURE_DATE

,a.EMAIL_SOURCE

,a.SOURCE_META

,a.SOURCE_DESCRIPTION

,a.VEHICLE

,a.CHANNEL

FROM $A$ a LEFT OUTER JOIN $B$ b ON a.RIID_=b.RIID_

WHERE B.RIID_ IS NULL ORDER BY a.CREATED_DATE_ ASC