Update MySQLNotes.md

MySQLNotes.md

@@ -57,11 +57,17 @@ SELECT * FROM people ORDER BY age DESC, first_name ASC;
 -- ALTER TABLE
 ALTER TABLE people ADD COLUMN weight FLOAT;
 ALTER TABLE people DROP COLUMN height;
+ALTER TABLE people MODIFY COLUMN height FLOAT;
+
 ALTER TABLE people ADD COLUMN height FLOAT AFTER first_name;
 ALTER TABLE people MODIFY COLUMN height FLOAT AFTER age;
+
 ALTER TABLE people ADD COLUMN id INT FIRST;
+ALTER TABLE people MODIFY COLUMN height FLOAT FIRST;
+
 ALTER TABLE people ADD COLUMN dob DATETIME;
 ALTER TABLE people CHANGE dob date_of_birth DATETIME;
+
 ALTER TABLE people ADD COLUMN id INT NOT NULL AUTO_INCREMENT PRIMARY KEY FIRST;
 
 -- AGGREGATION