In the rare case where the index becomes corrupted (which can signal itself by weird
search results or crashes), the index files need to be erased before restarting a clean
indexing pass. Just delete the xapiandb directory (see
next section), or, alternatively, start the
next recollindex with the
-z option, which will reset the database before indexing. The difference
between the two methods is that the second will not change the current index format, which
may be undesirable if a newer format is supported by the Xapian version.
