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Wildcard at the Beginning of a searchterm -Lucene

Tags:

lucene.net

As far as i know lucene(.net) doesn't support the wildcard at the beginning of a searchterm --> http://lucene.apache.org/java/2_0_0/queryparsersyntax.html "Note: You cannot use a * or ? symbol as the first character of a search."

for example *myword

maybe because it's quiet difficult to search "everything" before the searchterm.

Despite that, We are looknig for a way to use the wildcard at the beginning. Does anyone know if this is possible?

One Thought was asearchterm, bsearchterm, ....z*searchterm ... but that seems a bit random to me.

thanks in advance

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tim Avatar asked Aug 05 '10 07:08

tim


1 Answers

Your question is tagged with Lucene.NET so I assume you mean the .NET version rather than the Java version.

Yes, you can have wildcards at the beginning of a search term by via

var queryParser = new QueryParser(LuceneVersion, "content", new StandardAnalyzer(LuceneVersion));
queryParser.SetAllowLeadingWildcard(true);

but you need to be aware of the performance consequences. Find more detailed source code in this blog.

Since Lucene.NET is a port of the Java version, I suspect you could use the same approach for the Java version. I didn't verify this, though.

like image 127
Manfred Avatar answered Nov 03 '22 02:11

Manfred