title: Datatype for time period
body: <p>I would like to insert time period into table column. For example: I've got a table with 7 columns, each column is a day of a week. Is there a possibility to create a datatype that is a time period for employees work hours? Let's say from 1AM to 8AM. Or in 24h system.</p>
  
  <p>If there is not, how should i deal with it?</p>