Querying and Updating different documents in MongoDB - mongodb

Question

I am new to MongoDB so please excuse my ignorance.
I have a mongoDB which contains a bunch of documents with something like this
["field": "blah", "version":"1" ...]
["field": "blah", "version":"2" ...]
["field": "blah", "version":"1"....]
["field": "blah1", "version":"10"...]
["field": "blah2", "version":"100"...]
["field": "blah3", "version":"1"....]
["field": "blah3", "version":"2"....]
["field": "blah2", "version":"1"....
I am trying to send a list of queries and fetch all the records as a batch. Is it possible to do so?
List<Docs> fetchDocs(Map<String, String> queries)
{
CriteriaContainer cc=null;
Query<Docs> query = this.mongoDao.createQuery(MyClass.class);
for (Map.Entry<String,String >entry : queries.entrySet())
{
if(cc ==null)
{
cc= query.criteria("Field").equal(entry.getKey()).and(query.criteria("version").equal(entry.getValue()));
}
else
{
cc.or(query.criteria("Field").equal(entry.getKey()).and(query.criteria("version").equal(entry.getValue()));)
}
}
query.and(cc);
List<Docs> doc = query.asList();
return doc;
}
I am not geting the correct list back. I am not sure if I have written this query correctly.
essentially, I want to fetch results or query like this
[{"Field":"blah,"version":1 } $or {"Field":"blah1", "version":10} ]
It should return me a list containing
["field": "blah", "version":"1" ....]
["field": "blah1", "version":"10"....]

Answer 1

Yes, this is definitely possible to do. The final query object will look more like this, however:
{$or: [{"field": "blah,"version":1 }, {"field":"blah1", "version":10} ]}
Notice the array of subqueries for the $or expression.
There are some quirks in Morphia will mean you have to wrap it in an $and clause. So your code would be like this:
Query q = dao.createQuery();
q.and(
q.or(subQuery1),
q.or(subQuery2),
...
);

Answer 2

I ended up fixing my query to this which worked. Wanted to share it with the rest
List<Docs> fetchDocs(Map<String, String> queries){
Criteria [] c = new Criteria[queries.size()];
Query<TUCacheDoc> query0 = this.mongoDao.createQuery(MyClass.class);
int counter=0;
for (Map.Entry<String, String> entry : inMap.entrySet()) {
Query<TUCacheDoc> queryC = this.mongoDao.createQuery(MyClass.class);
String key= entry.getKey();
String val= entry.getValue();
Criteria cC = queryC.criteria("field").equal(key).criteria("version").equal(val);
c[counter]=cC;
counter++;
}
query0.or(c);
List<TUCacheDoc> qresult = query0.asList();
return qresult;
}