Fast incremental reindexing grabs only the files that have changed!
All PicoSearch accounts can reindex at any time, online or offline, just by pushing a manual button in the account manager. Paying accounts can additionally set automatic scheduled reindexing for daily, twice-weekly, weekly, or monthly reindexing (contact us if you need more than once per day).
For Professional and Premium accounts, PicoSearch uses Incremental Reindexing to be smart about fetching only the files that have changed on your website. PicoSearch compares the stored file information from your search engine's last indexing, to the Last-Modified Date reported by your server in the new indexing. If the file dates are the same, then PicoSearch will use the stored file version, saving you up to 60% in downloading time. If your server's HTTP header is not reporting the Last-Modified Date, but is reporting Content-Length, then PicoSearch may still decide to keep the previous version, but only if file lengths are absolutely identical. In all other cases, the file will be fully downloaded again from your server.
By default, the display and sorting of file dates in the search results also relies on the Last-Modified Date reported by your server. But while that file date line can be configured to get dates from other sources, incremental reindexing can only be driven by the HTTP header's Last-Modified Date and Content-Length as described above. So it's a good idea for your server to either report the Last-Modified Dates correctly or at least not at all. If your server were badly configured to always report the same incorrect date, you might have a hard time indexing new content. Contact us if you think your server has problems that may require your PicoSearch to always use Full Reindexings.
PicoSearch looks closely at many factors to make sure that all links and text are correctly re-evaluated in the context of each new incremental reindexing. Any account manager changes that require a Full Reindexing will automatically do so. In case you ever suspect that a previous file download was inappropriately retained, you can try overriding your account manager's Reindex Web Site section MODE option to fully reindex on the next reindexing (either online, offline, or scheduled). Again, you may contact us if you think your account would benefit from being set to always use Full Reindexings.
In this way you can be sure that Incremental Reindexing will accurately save time and bandwidth for both your website and PicoSearch.