Using MySQL triggers to log all table changes to a secondary table

The insert syntax is

INSERT INTO table (columns_list) VALUES (values_list)

so your insert would look something like this (i'm not a MySQL expert but you can fit the query):

INSERT INTO data_tracking (`data_id` , `field` , `old_value` , `new_value` , `modified` ) VALUES (NEW.data_id, 'field1', OLD.field, NEW.field, CURRENT_DATETIME());

And repeat it for variation on field2 and field3

I think this would be the complete trigger, please try:

DELIMITER $$DROP TRIGGER `update_data `$$CREATE TRIGGER `update_data` AFTER UPDATE on `data_table`FOR EACH ROWBEGIN    IF (NEW.field1 != OLD.field1) THEN        INSERT INTO data_tracking             (`data_id` , `field` , `old_value` , `new_value` , `modified` )         VALUES             (NEW.data_id, "field1", OLD.field1, NEW.field1, NOW());    END IF;    IF (NEW.field2 != OLD.field2) THEN        INSERT INTO data_tracking             (`data_id` , `field` , `old_value` , `new_value` , `modified` )         VALUES             (NEW.data_id, "field2", OLD.field2, NEW.field2, NOW());    END IF;    IF (NEW.field3 != OLD.field3) THEN        INSERT INTO data_tracking             (`data_id` , `field` , `old_value` , `new_value` , `modified` )         VALUES             (NEW.data_id, "field3", OLD.field3, NEW.field3, NOW());    END IF;END$$DELIMITER ;