First, kudos for making this test and attaching it. If nothing else that
makesme curious to see whether I really understand what's going on or not.
I think you're looking at the wrong tab in Luke <G>... I modified your test
write to an FSDir. When you look at the "overview" tab, you'll see three
"ghostbusters", "parenth" and "eses". Terms are the things searched. The
places you're seeing "(Parenth+esis" is when Luke is trying to show you the
*document* and using the stored values.
For instance, in the "documents" tab, when you see your document, the
column is "(Parenth+eses", but that's the stored value, not the indexed
If you click the "first term" button in the upper right, you'll see "eses",
through the next terms shows "ghostbusters" and "parenth".
Have you tried WhitespaceAnalyzer? That one breaks things up only on
whitespace. Beware, that that's *all* it does so things like case can mess
you up. But you can easily construct your own Analyzer and/or pre-process
your inputs (both at index and query time) to handle case, whichever
you're more comfortable with (making your own analyzer is much more
All making your own analyzer will have to do in this case is string together
some of the pre-existing filters into a TokenStream in a class subclassed
So no, this is NOT only a index issue, it's an Analyzer issue (hence the
advice to use the same analyzer at index and query times). The behavior
is as expected and I doubt it's worth a JIRA since constructing special-
purpose analyzer and using it is pretty easy. Although if you can convince
the committers that this is a common enough use case and wanted to
create such an analyzer they'd be happy to put it in the contrib area.
On Thu, May 14, 2009 at 9:19 PM, Ari Miller wrote:
I buy your theory that StandardAnalyzer is breaking up the stream, and that
this might be an indexing issue, rather than a query issue. When I look at
my index in Luke, as far as I can tell the literal (Parenth+eses is stored,
not the broken up tokens. Also, I can't seem to find an Analyzer that
doesn't suffer from these issues.
I've created a standalone test case that demonstrates the current
behavior. I've attached it to this email. It should just require junit and
lucene. It might actually be useful in general for anyone trying to figure
out various Lucene behaviors.
At a high level, am I correctly understanding that Lucene doesn't support
searching on indexed special characters without significant additional
machinations? If so, has anyone gone through those machinations and posted
a link :)? Given the test case, is this worthy of a JIRA issue?
On Thu, May 14, 2009 at 4:59 PM, Erick Erickson wrote:
I suspect that what's happening is that StandardAnalyzer is breaking
your stream up on the "odd" characters. All escaping them on the
query does is insure that they're not interpreted by the parser as (in
this case), the beginning of a group and a MUST operator. So, I
claim it correctly feeds (Parenth+eses to the analyzer, which then
breaks it up into the tokens you indicated.
Assuming you've tried to index this exact string with StandardAnalyzer,
if you looked in your index (say with Luke), you'd see that "parenth" and
"esis" were the tokens indexed.
Warning: I haven't used the ngram tokenizers, so I know just enough to
be dangerous. That said, you could tokenize these as ngrams. I'm not sure
what the base ngram tokenizer does with your special characters, but you
could pretty easily create your own analyzer that spits out, say, 2-(or
grams and use that to index and search, possibly using a second field(s)
the data you wanted to treat this way...
On Thu, May 14, 2009 at 7:18 PM, Ari Miller wrote:
Say I have a book title, literally:
How would I do a search to find exactly that book title, given the presence
of the ( and + ? QueryParser.escape isn't working.
I would expect to be able to search for (Parenth+eses [exact match] or
(Parenth+e [partial match]
I can use QueryParser.escape to escape out the user search term, but
that to QueryParser with a StandardAnalyzer doesn't return what I would
For example, (Parenth+eses --> QueryParser.escape --> \(Parenth\+eses, when
Note that the escaped special characters seem to be turned into spaces, not
Up to this point, even attempting to directly create an appropriate query
(PrefixQuery, PhraseQuery, TermQuery, etc.), I've been unable to come up
with a query that will match the text with special characters and only that
My longer term goal is to be able to take a user search term, identify it
a literal term (nothing inside should be treated as lucene special
characters), and do a PrefixQuery with that literal term.
In case it matters, the field I'm searching on is indexed, tokenized, and
Potentially relevant existing JIRA issues:http://issues.apache.org/jira/browse/LUCENE-271http://issues.apache.org/jira/browse/LUCENE-588
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