What important date-time functions are missing from Calcite? Calcite has quite a few functions, including: * EXTRACT(<time-unit> FROM <date-time>) * FLOOR(<date-time> TO <time-unit>) * CEIL(<date-time> TO <time-unit>) * CAST(<date-time> TO <data-type>) * <date-time> + <interval> * <date-time> - <interval> * (<date-time> - <date-time>) <time-unit> [ TO <time-unit> ]
But there are gaps. For instances, there doesn't seem to be a way to convert a time to day of the week. So, it would be useful if we implemented DAYOFWEEK a la MySQL [ https://dev.mysql.com/doc/refman/5.5/en/date-and-time-functions.html ]. What other functions are needed? I'm not interested in implementing every possible date-time function in every database. (We don't need DATEDIFF, because we have interval arithmetic.) I just want to make sure that there is a way to achieve all of the common operations. Julian
