>>>What data-type do you use if you need if you need an index on that field?
>>
>>I forget the reason, but you do not index bit fields in SQL Server.
>
>The same reason you don't in VFP. Bit fields have only two possible values. Indexing on this field will result in the query optimizier using too many rows when determing a final result set.
>
>Example:
>Say you have an even distribution of 1s and 0s. An intermediate result will be built with approximately half of the rows in your table. This result set would then have to be matched with the results sets from the other selection criteria. If you took out the bit index, then the final result would be processed to determine what rows matched the bit flag.
>
>Just my opinion.

Does this also hold true with a bit field index with high selectivity? In other words, what happens with 1,000,000 records, and only 20 or 30 have a bit field = 1?