How to copy a column from a table in one database to a table in another database
Assuming the destination column exists and you are aligning the copied data to the row ID.
Alias used as a safeguard.
update myDestinationTable Set myColumn = mySourceTableAlias.URL
from myDestinationTable
inner join myOtherDatabase.dbo.mySourceTable mySourceTableAlias on myDestinationTable.ID = mySourceTableAlias.ID
See also