Adds seconds to a datetime
Changes format of hours from 24-hours to 12-hours
Constructs a datetime value from a year, month, day, hour, minute, and second
Calculates the difference between two datetimes in seconds
Transforms a datetime into a string timestamp in the form "2018-03-25 23:35:04"
Destructs a datetime value into a year, month, day, weekday, hour, minute, and second