Actualizar el servidor SQL desde otra tabla
UPDATE t1
SET t1.column = t2.column
FROM Table1 t1
INNER JOIN Table2 t2 ON t1.id = t2.id;
Inexpensive Iguana
UPDATE t1
SET t1.column = t2.column
FROM Table1 t1
INNER JOIN Table2 t2 ON t1.id = t2.id;-- SQL Server
UPDATE Sales_Import
SET Sales_Import.AccountNumber = RAN.AccountNumber
FROM Sales_Import SI
INNER JOIN RetrieveAccountNumber RAN
ON SI.LeadID = RAN.LeadID;
-- MySQL & MariaDB
UPDATE Sales_Import SI, RetrieveAccountNumber RAN
SET SI.AccountNumber = RAN.AccountNumber
WHERE SI.LeadID = RAN.LeadID;