-- update inner where
UPDATE business AS b
INNER JOIN business_geocode AS g ON b.business_id = g.business_id
SET b.mapx = g.latitude,
b.mapy = g.longitude
WHERE (b.mapx = '' or b.mapx = 0) and
g.latitude > 0
-- http://stackoverflow.com/questions/8057565/mysql-update-statement-inner-join-tables
-- update inner
UPDATE wifcms_mod_geodata__address as t2
INNER JOIN wifcms_mod_ads_areas_alias as t1
ON t1.aa_id = t2.aa_id
SET t2.area_id = t1.area_id
-- http://dba.stackexchange.com/questions/21152/how-to-update-one-table-based-on-another-tables-values-on-the-fly