mysql update multiple rows from select same table code example

Example 1: mysql update multiple rows with different values

UPDATE config
   SET config_value = CASE config_name 
                      WHEN 'name1' THEN 'value' 
                      WHEN 'name2' THEN 'value2' 
                      ELSE config_value
                      END
 WHERE config_name IN('name1', 'name2');

Example 2: mysql update one table from another table multiple columns

update  tabe2 set subject_id = (SELECT GROUP_CONCAT(sub_id SEPARATOR ', ') as sub_id FROM tabe1)