update select문

UPDATE table1 a
SET a.col1 = (SELECT col1 FROM table2 WHERE col2 = a.col2)
WHERE a.col2 IN (SELECT col2 FROM table2)

UPDATE table1 a
SET ( col1, col2 ) = ( SELECT col1, col2 FROM table2 b WHERE b.col3=a.col3 ) 
WHERE a.col3 IN ( SELECT col3 FROM table2 )