On Sun, Apr 27, 2008 at 9:01 AM, Jean-David Beyer <jeandavid8@verizon.net> wrote: > In another thread, the O.P. had a question about a large table with over 100 > columns. Is this usual? Whenever I make a database, which is not often, it > ends up with tables that rarely have over to columns, and usually less than > that. When normalized, my tables rarely get very wide.
Yes, even in several well-normalized schemas I've seen tables with over 250 columns.
> Without criticising the O.P., since I know nothing about his application, I > am curious how it comes about that such a wide table is justified.
The few applications I've seen with large tables were an insurance system, an manufacturing system, and a sensor-recording system (which was more optimal to store as an attribute-per-instance-of-time than a separate tuple containing the time, sensor, and value).
