what does the following sql statement execute

SELECT DISTINCT 
	C.customer_key,
	SR.source_id,
	SR.wholesaler_code,
	SR.wholesaler_branch_code,
	SR.customer_code,
	SR.customer_name,
	SR.address_1+', '+ SR.address_2+', '+ CASE WHEN SR.address_3 = '' OR SR.address_3 IS NULL THEN '' ELSE SR.address_3 END  +', '+postal_code AS [address],
	ISNULL(M.orgcode,1) AS orgcode,
	B.bricknumber AS brick_id,
	'N' as customer_comark,
	'N' AS customer_growth,
	'N' AS customer_pn
--SELECT DISTINCT SR.*,c.source_ind ,c.wholesaler_branch_code--,W.wholesaler_branch_code
FROM stagedw.dbo.wholesaler_customer_pharmed_kzn_src SR --(889 row(s) affected)
INNER JOIN idxdw.dbo.idx_aspen_inmarket_customer C
	ON  SR.source_id = C.source_ind --'PHARM'
	AND SR.wholesaler_code = C.wholesaler_code
	AND SR.wholesaler_branch_code = C.wholesaler_branch_code
	AND SR.customer_code = C.customer_code
LEFT OUTER JOIN edw.dbo.dim_aspen_inmarket_customer IC
	ON  SR.customer_code = IC.customer_code
	AND SR.wholesaler_code = IC.wholesaler_code
	AND SR.wholesaler_code = IC.wholesaler_code
	AND SR.source_id = IC.source_id 
LEFT OUTER JOIN JNBVDW02A.edw.dbo.dim_ims_gsk_wholesaler W
	ON 	
		--C.wholesaler_branch_code = 'KZN' -- GTNG needs to be added.. W.wholesaler_branch_code
	--AND
	 C.wholesaler_code = W.wholesaler_code
LEFT OUTER JOIN (SELECT  wholesalerid,accnumber,orgcode,updatetype,d.wholesalerlinkid
				 FROM JNBVDW02A.pharmacare.dbo.medpages_wholesaler_org_link t 
					LEFT JOIN stagedw.dbo.st_medpages_wholesaler_org_link d
						ON d.wholesalerlinkid = t.wholesalerlinkid
					WHERE d.wholesalerlinkid IS NULL AND updatetype <> 'D'
				) AS M
	ON W.wholesaler_distributor_code = M.wholesalerid
	AND c.customer_code = M.accnumber
LEFT OUTER JOIN (SELECT 
					DISTINCT orgcode,bricknumber 
				FROM JNBVDW02A.pharmacare.dbo.medpages_organisation
				) AS B
	ON M.orgcode = B.orgcode
WHERE IC.customer_code IS NULL