Wednesday, March 11, 2009

Time

Many years ago (about 6 or 7 really), my boss sent me this diagram from the Oracle Docs. In particular, he wanted me to focus on the times table. After a few emails exchanged I finally figured out what he was asking, well sort of. He had used a table called periods described below:
CREATE TABLE periods
(
periodid NUMBER(10),
datefrom DATE,
datethru DATE,
periodtype VARCHAR2(30),--DAY, MONTH, YEAR, ETC
);
This was primarily (solely perhaps) used for reporting. He had actually built this pretty cool page for the business to be able to drill down on certain key aspects of the business. That may have been my first real exposure to Data Warehousing.

The point he was trying to make though was that this TIMES table was a flattened version of his PERIODS table. If you have one date, you can see how that date fell in multiple dimensions. What month it took place. What quarter it took place. What day of the year (1-365) it took place. All with just a single row of data.

The TIMES table, or dimension is a standard in data warehousing for exactly this reason.

I've been working on our "data warehouse" (replicated tables from the OLTP) and had been using the PERIODS methodology. There is a time dimension, but it's not populated at this time.

Since I am by no means a data warehousing expert and I have virtually no experience with OBIEE, I'm trying to come up with a way to help bridge both those gaps. Use OBIEE against the relational tables to help me learn OBIEE. I've created a couple of small subject areas so far and demo'd them to the users and they love it. So do I in fact.

Anyway, back to my topic. As I was thinking about TIME, I began to reminisce about time and how I got started. It's funny how I remember that exact moment sitting there with my feet propped up on my desk in my garage office.

Was there a point to all this? I don't think so. Just me rambling on.

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