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Lucene does not work for MUSTNOT Boolean query

I created a lucene indexes for set of data and trying to retrieve results from that.
When I do a boolean query with SHOULD, lucene returns me expected result.
eg: (title:"america")
But on the other hand when I do a MUST_NOT query, it returns me empty results even though there are lot of data which satisfy this criteria.
(-title:"america")
I think I am doing some silly mistake but not able to figure it out so far. Could someone please give some pointers.

Understood the issue. I should combine MUSt NoT with some other operators.
Quote from https://www.bookdepository.com/Lucene-in-Action-Erik-Hatcher/9781933988177?redirected=true&utm_medium=Google&utm_campaign=Base3&utm_source=BE&utm_content=Lucene-in-Action&selectCurrency=EUR&w=AF4UAU960P6LMLA8VCZZ&gclid=Cj0KCQjwuL_8BRCXARIsAGiC51C8OdXsVpJbYRfodiFcGFEl2FKylqh2MvBjnHs9T5fVfMmDzZXbU4oaAisFEALw_wcB
Placing a NOT in front of a term excludes documents matching the following term.
Negating a term must be combined with at
least one non-negated term to return docu-
ments; in other words, it isn’t possible to
use a query like NOT term to find all docu-
ments that don’t contain a term.

How to get result set by checking a specific element in an aggregated array using JOOQ?

I want to filter results by a specific value in the aggregated array in the query.
Here is a little description of the problem.
Section belongs to the garden. Garden belongs to District and District belongs to the province.
Users have multiple sections. Those sections belong to their gardens and they are to their Districts and them to Province.
I want to get user ids that have value 2 in district array.
I tried to use any operator but it doesn't work properly. (syntax error)
Any help would be appreciated.
ps: This is possible writing using plain SQL
rs = dslContext.select(
field("user_id"),
field("gardens_array"),
field("province_array"),
field("district_array"))
.from(table(select(
arrayAggDistinct(field("garden")).as("gardens_array"),
arrayAggDistinct(field("province")).as("province_array"),
arrayAggDistinct(field("distict")).as("district_array"))
.from(table("lst.user"))
.leftJoin(table(select(
field("section.user_id").as("user_id"),
field("garden.garden").as("garden"),
field("garden.province").as("province"),
field("garden.distict").as("distict"))
.from(table("lst.section"))
.leftJoin("lst.garden")
.on(field("section.garden").eq(field("garden.garden")))
.leftJoin("lst.district")
.on(field("district.district").eq(field("garden.district")))).as("lo"))
.on(field("user.user_id").eq(field("lo.user_id")))
.groupBy(field("user.user_id"))).as("joined_table"))
.where(val(2).equal(DSL.any("district_array"))
.fetch()
.intoResultSet();

Your code is calling DSL.any(T...), which corresponds to the expression any(?) in PostgreSQL, where the bind value is a String[] in your case. But you don't want "district_array" to be a bind value, you want it to be a column reference. So, either, you assign your arrayAggDistinct() expression to a local variable and reuse that, or you re-use your field("district_array") expression or replicate it:
val(2).equal(DSL.any(field("district_array", Integer[].class)))
Notice that it's usually a good idea to be explicit about data types (e.g. Integer[].class) when working with the plain SQL templating API, or even better, use the code generator.

Accessing Neo4j List in Java After Query

I don't have much code to post, and I'm quite confused on where to start. There's a lot of documentation online and I can't seem to find what I'm looking for.
Suppose I have this query result saved into a StatementResult variable:
result = session.run("MATCH (n:person {tag1: 'Person1'})"
+ "RETURN [(n)-->(b) WHERE b:type1 | m.tag2]")
In the Neo4j browser, this returns a list of exactly what I'm looking for. My question is how we can access this in Java. I know how to access single values, but not a list of this type.
Any help would be appreciated.
Thanks.

Usually you just iterate over the statement results, to access each record and then with each record you can access each named column. You didn't use any names.
The column will return Value objects which you then can turn into the types you expect, so in your case into a list with asList().
See the API docs for StatementResult and Value.asList()
also your statement is not correct you probably meant b where you wrote m and you need to name your column to access it

Sort the values by Date in mongodb

I am new to mongodb and I am trying to sort all my rows by date. I have records from mixed sources and I trying to sort it separately. I didn't update the dateCreated while writing into db for some records. Later I found and I added dateCreated to all my records in the db. Say I have total of 4000 records, first 1000 I don't have dateCreated. Latest 3000 has that column. Here I am trying to get the last Updated record using dateCreated column. Here is my code.
db.person.find({"source":"Naukri"}&{dateCreated:{$exists:true}}).sort({dateCreated: 1}).limit(10)
This code retruns me some results (from that 1000 records) where I can't see that dateCreated column at all. Moreover if I change (-1) here {dateCreated: -1} I am getting results from some other source, but not Naukri.
So I need help this cases,
How do I sort by dateCreated to get the latest updated record and by sources also.
I am using Java API to get the records from Mongo. I'd be grateful if someone helps me to find how I will use the same query with java also.
Hope my question is clear. Thanks in advance.

From the documentation you will (and you will, won't you - nod yes) read, you will find that the first argument to the find command you are using is what is called a query document. In this document you are specifying a list of fields and conditions, "comma" separated, which is the equivalent of an and condition in declarative syntax such as SQL.
The problem with your query is it was not valid, and did not match anything. The correct syntax would be as follows:
db.person.find({"source":"Naukri", dateCreated:{$exists:true}})
.sort({dateCreated: -1})
.limit(10)
So now this will filter by the value provided for "source" and where the "dateCreated" field exists, meaning it is there and it contains something.
I recommend looking at the links below, the first of the two concerned with structuring mongoDB queries and the find method and it's arguments. All of the functionality translates to every language implementation.
As for the Java API and how to use, there are different methods depending on which you are comfortable with. The API provides a BasicDBObject class which is more or less equivalent to the JSON document notation, and is sort of a hashmap concept. For something a bit more along the lines of the shell methods and a helper to be a little more like some of the dynamic languages approach, there is the QueryBuilder class which the last two links give example and information on. These allow chaining to make your query more readable.
There are many examples on Stack Overflow alone. I suggest you take a look.
http://docs.mongodb.org/manual/tutorial/query-documents/
http://docs.mongodb.org/manual/reference/method/db.collection.find/
How to do this MongoDB query using java?
http://api.mongodb.org/java/2.2/com/mongodb/QueryBuilder.html

Your query is not correct.Update it as follows :
db.person.find({"source":"Naukri", dateCreated:{$exists:true}}).sort({dateCreated: 1}).limit(10)
In Java, you can do it as follows :
Mongo mongo = ...
DB db = mongo.getDB("yourDbName");
DBCollection coll = db.getCollection("person");
DBObject query = new BasicDBObject();
query.put("source", "Naukri");
query.put("dateCreated", new BasicDBObject($exists : true));
DBCursor cur = coll.find(query).sort(new BasicDBObject("dateCreated", 1)).limit(10);
while(cur.hasNext()) {
DBObject obj = cur.next();
// Get data from the result object here
}

sort and limit castor query

I am attempting to return a single object via castor query that has the earliest date.
This is the sort of thing I have been trying:
SELECT p FROM model.objects.Product p LIMIT $1 WHERE p.status=$2 ORDER BY p.statusDate;
This results in: org.exolab.castor.jdo.oql.OQLSyntaxException: An incorrect token type was found near WHERE (found KEYWORD_WHERE, but expected END_OF_QUERY
I am using version 0.9.6 which I believe supports this kind of thing.
Any hints or pointers much appreciated.

As per my comment, it indeed appears that the LIMIT clause must appear after the ORDER BY clause. See the Castor query syntax.