Oh, you asked about the meaning of the plus sign too.
Well, I recommend reading a book* or any tutorial, but the clauses of
boolean queries there are three occurences, SHOULD, MUST and MUST_NOT, that
roughly translate to OR, AND, and NOT, respectively.
The plus sign means MUST, the minus sign means MUST_NOT and the absence of
both means SHOULD (it may or may not match any indexed term)
For example:
- a query like "text:(toys AND child)" will be translated like "+text:toys
+text:child" (both terms are required to match)
- a query like "text:(toys OR child)" will be translated as "text:toys
text:child" (both terms or only one term can match, that is more or less
equivalent to OR);
- a query like "text:toys NOT text:child" will be translated as "text:toys
-text:child" (try to match text:toys, but also remove the docs that match
text:child from the result set);
* = Lucene book, Solr book and Relevant Search book are excellent resources!
Edward
Em qua, 22 de jan de 2020 15:07, Edward Ribeiro <edward.ribe...@gmail.com>
escreveu:
> If you are using Lucene's BooleanQueryBuilder then you need to do nesting
> of your queries (roughly, a builder for each query enclosed in
> "parenthesis").
>
> A query like (text:child AND text:toys) OR age:12 would be:
>
> Query query1 = new TermQuery(new Term("text", "toys"));
> Query query2 = new TermQuery(new Term("text", "children"));
> Query query3 = new TermQuery(new Term("age", "12"));
>
> BooleanQuery.Builder andBuilder = new BooleanQuery.Builder();
> andBuilder.add(query1, BooleanClause.Occur.MUST);
> andBuilder.add(query2, BooleanClause.Occur.MUST);
>
> BooleanQuery.Builder builder = new BooleanQuery.Builder();
> builder.add(andBuilder.build(), BooleanClause.Occur.SHOULD);
> builder.add(query3, BooleanClause.Occur.SHOULD);
>
> BooleanQuery booleanQuery = builder.build();
>
> This booleanQuery.toString() will be:
>
> (+text:toys +text:children) age:12
>
> That is the parsing of "(text:child AND text:toys) OR age:12"
>
>
> Edward
>
> On Tue, Jan 21, 2020 at 5:24 PM Arnold Bronley <arnoldbron...@gmail.com>
> wrote:
> >
> > Hi,
> >
> > BooleanQueryBuilder is not adding parenthesis around the query. It
> > only adds + sign at the start of the query but not the parentheses around
> > the query. Why is that? How should I add it?
> >
> > booleanQueryBuilder.add(query, BooleanClause.Occur.MUST)
>
