In Ruby on Rails, what's the difference between DateTime, Timestamp, Time and Date?

Question

In my experience, getting dates/times right when programming is always fraught with danger and difficulity.

Ruby and Rails have always eluded me on this one, if onl

Answer 1

Here is an awesome and precise explanation I found.

TIMESTAMP used to track changes of records, and update every time when the record is changed. DATETIME used to store specific and static value which is not affected by any changes in records.

TIMESTAMP also affected by different TIME ZONE related setting. DATETIME is constant.

TIMESTAMP internally converted a current time zone to UTC for storage, and during retrieval convert the back to the current time zone. DATETIME can not do this.

TIMESTAMP is 4 bytes and DATETIME is 8 bytes.

TIMESTAMP supported range: ‘1970-01-01 00:00:01′ UTC to ‘2038-01-19 03:14:07′ UTC DATETIME supported range: ‘1000-01-01 00:00:00′ to ‘9999-12-31 23:59:59′

source: https://www.dbrnd.com/2015/09/difference-between-datetime-and-timestamp-in-mysql/#:~:text=DATETIME%20vs%20TIMESTAMP%3A,DATETIME%20is%20constant.

Also...

table with different column "date" types and corresponding rails migration types depending on the database