FACT table with Timezone

[dshivhare]

Reference: thread353-1421422


Hello All,

Our OLTP database records transactions with a UTC/GMT timestamp. We are just starting design for a new data warehouse and we're trying to design how our date and time dimensions will work. We need to be able to support multiple timezones. We were initially thinking that we would have one wide combined date dimension down to one day (24hrs) granularity.

We are currently using a FACT table that aggregates information (via ETL) on daily basis in UTC time but the problem is that how to aggregate the data by each timezone which recalculates (via ETL) the data for that day.

Does anyone know of a way to store the daily aggregation but still respect the numbers and totals for each timezones?

Thanks to all who take the time to respond.

 

[johnherman]

You could consider denormalizing the Julian date into the FACT, that Julian date being based on the local date rather than the UTC date. Then you would have the UTC and the Julian date both in the FACT. The advantage being that you don't need to join to the date dimension when doing local time aggregations.

==================================
adaptive uber info galaxies (bigger, better, faster than agile big data clouds)