To bad you have already selected the database system. It is alway best to think of requirements and then select parts the do what you need. I would have selected a DMBS that allows the user to define his own types and operators on those types. THen I'd define a type called "Precision time" that works at what ever level I need, nano or een Femtoseconds. You then define the greater then and less then operators and soon andthen can use the type in SQL querries. THis ability to define types is in many DBMSes certianly Ocrcle and PostgreSQL. The later is free and open source. You might conceder it. Postgres has a handy built-in type "Geo Location" and operators for things like "distance" and "point inside bounding box" and many others operators for using geographic points and regions.
Lacking a DBMS that allows you to extend the built-in types and operators tou can simply store your data in multiple columns. Make a table called "event_time" and make a column for julian day, seconds and nanoseconds. Or if you absolutely need one field for date-time then use a long ASCII string to record julian date with as many decimal points as you need. If you MUST squeeze store the date/time in a 64 bit float then use the start of you project as the "epoc" Set it up so that Jan 1, 2011 is "zero" and you will squeeze a few more decimal places into 64 bits. My first choice would be to move to PostgreSQL. THen you can define the classes and operators you needs and then you can take advance of SQL to do must of you work. It's open source to the cost is nothing Chris Albertson Redondo Beach, California _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
