Cross Table Update with MySQL

update a table with data from another table

UPDATE compounds AS c , excel AS e
SET c.Price_1 = e.price
WHERE c.catalog_no = e.cno;



update webcas.all_cas as wac, webcas.compounds as wc, pubchem.compounds as pc
set wc.smiles=pc.smiles
where wc.mol_id=wac.id and pc.pub_id=wac.source_id ;