Re: Opinons/Philosophy on adding flags to table to reduce queries?

Hi Jeff,

"Jeff Wilson" <jwilson2000_at_home.com> wrote in message news:<Xgc07.288435$p33.5772965_at_news1.sttls1.wa.home.com>...
> What is the conventional wisdom regarding adding a boolean column to a table
> that is simply the result of a test on the values in about 6 other columns?

There certainly is no convention on this. In some cases it can be a very good idea.

The big advantage of such a flag is, that you can use a nonunique index on the flag to speed up your query.

> The data in this table is fixed so I don't have to worry about an update
> affecting theboolean.

Even if it weren't fixed, you could put a trigger on that table, that sets the flag after each insert or update.

> Would only a purist avoid something like this? Are there considerations
> here I'm missing?

Nope, good idea :-)

Ciao,
Hans

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