FAQ #2581, published on 2002-10-15
WINDEV
When is it preferable to use a filter over a query?
If the filter condition contains OR's or <> conditions, use a query.
File reading will be reduced to a minimum because HF chooses
automatically the best browsing key, and this key might change during
the entire execution of the query in order to read the least
number of records possible.

If the condition contains neither OR nor <>, the number of readings will
be the same as for a filter, a view or a query.
See also : wd7, filter, query, key