function helps with building queries in pieces. WANT should be a list of
column names we should output, appropriately qualified if there are
multiple tables; TAB should be a list of table names, in the form `FOO as
function helps with building queries in pieces. WANT should be a list of
column names we should output, appropriately qualified if there are
multiple tables; TAB should be a list of table names, in the form `FOO as