Are there any differences between the two? Or can you use it interchangeably?

Hi Japhet! Thanks for reaching out. They do different things, so: ALTER COLUMN Used to set or remove the default value for a column. Example: ALTER TABLE MyTable ALTER COLUMN foo SET DEFAULT 'bar'; ALTER TABLE MyTable ALTER COLUMN foo DROP DEFAULT; CHANGE COLUMN Used to rename a column, change its datatype, or move it within the schema. Example: ALTER TABLE MyTable CHANGE COLUMN foo bar VARCHAR(32) NOT NULL FIRST; ALTER TABLE MyTable CHANGE COLUMN foo bar VARCHAR(32) NOT NULL AFTER baz; Hope this helps. Best, Tsvetelin

Change column was used to add default and alter column to drop default in the video you are saying alter column is for adding or dropping defaults. ALTER TABLE customers CHANGE COLUMN number_of_complaints number_of_complaints int DEFAULT 0; ALTER TABLE customers ALTER COLUMN number_of_complaints DROP DEFAULT;