I am using mongodb with Java 3.0 driver. I have a scenario where I have to perform logical and i.e, $and on my queries. For example, I have two documents already created and I am trying to do something like this:
iterable = mongoDatabase.getCollection("restaurants").find(
new Document("$and", asList(abc,
updatedDocumentTypeOne)));
where abc is one document and updatedDocumentTypeOne is another document. I found this in mongodb manual but I am getting error as first create asList Method.
Or how to replicate the following in Java:
db.inventory.find( {
$and : [
{ $or : [ { price : 0.99 }, { price : 1.99 } ] },
{ $or : [ { sale : true }, { qty : { $lt : 20 } } ] }
]
} )`
You can also try the code below that adds a filter for query replication in Java:
// Where db is the object reference of "inventory" collection's database
MongoCollection<Document> inventory = db.getCollection("inventory");
//List for result return
List<Document> result = new ArrayList<Document>();
//Query replication in Java and return result into the list
inventory.find(Filters.and(
Filters.or(Filters.eq("price", 0.99),Filters.eq("price", "1.99")),
Filters.or(Filters.eq("sale", true),Filters.lt("qty", 20))
)).into(result);
Change from asList() to Arrays.asList()
Instead of writing Arrays.asList(), you have specified as asList(). So compiler is searching for the method asList(), which is NOT available.
Check the below code :
iterable = mongoDatabase.getCollection("restaurants").find(
new Document("$and", Arrays.asList(abc,
updatedDocumentTypeOne)));
For your above query, You can code as below :
/* First OR condition */
Document price1 = new BasicDBObject("price",0.99);
Document price2 = new BasicDBObject("price",1.99);
BasicDBList or_first = new BasicDBList();
or_first.add(price1);
or_first.add(price2);
DBObject query = new BasicDBObject("$or", or_first);
/* Second OR condition */
boolean val = true;
Document sale = new BasicDBObject("sale",val);
Document qty = new BasicDBObject("qty", new BasicDocument("$lt",20));
BasicDBList or_second = new BasicDBList();
or_second.add(sale);
or_second.add(qty);
DBObject query = new BasicDBObject("$or", or_second);
/* AND condition logic */
BasicDBList and_op = new BasicDBList();
and_op.add(or_first);
and_op.add(or_second);
iterable = mongoDatabase.getCollection("restaurants").find( new Document("$and", and_op ));
Related
This is my current code
Document bitcoin = new Document("Currency", "Bitcoin").append("Values", Arrays.asList());
//bitCoinCollection.insertOne(bitcoin);
for(int i = 0; i<100;i++){
BasicDBObject setNewFieldQuery = new BasicDBObject()
.append("$set", new BasicDBObject().append("value", 100));
mongoClient.getDatabase("Binance").getCollection("Binance")
.updateOne(new BasicDBObject().append("_id", "tjena"), setNewFieldQuery);
}
It doesnt add any values to the excisting arraylist... is there a way to add it to an excisting arraylist in a document? Thanks in advance
For this sample collection of one document with an array field using MongoDB Java driver:
{ _id: 1, fruits: [ "orange", "banana" ] }
The following Java code adds one new element to the fruits array:
Bson update = push("fruits", "guava");
Bson filter = eq("_id", new Integer(1));
UpdateResult result = collection.updateOne(filter, update);
To add multiple elements all at once from a List collection:
Bson update = pushEach("fruits", Arrays.asList("grape", "apple", "peach"));
Bson filter = eq("_id", new Integer(1));
UpdateResult result = collection.updateOne(filter, update);
I have tried to fetch data for the particular column value in the mongo document but its displaying whole data.
Following is the mongo document:
{
"_id" : ObjectId("59db2321811a592384865711"),
"User_ID" : "demo",
"Project_ID" : "demo-1",
"Project_Information" : {
"Project_Description" : "Sample",
"Primary_Building_Type" : "Office",
"State" : "AR",
"Analysis_Type" : "1",
"Project_Billing_Number" : "WY",
"Country" : "USA",
"Climate_Zone" : "3A",
"Zip_Code" : "71611"
"City" : "WA",
"Units" : "IP"
}
}
I want to fetch the following output:
[
{
"User_ID": "demo",
"Project_Description": "Sample"
}]
I have tried using dot: Project_Information.Project_Description.The code is as below:
public Object[] addDemo1(String User_ID) throws Exception {
DB db = ConnectToDB.getConnection();
Properties prop = new Properties();
InputStream input = null;
input = GetProjectStatus.class.getClassLoader().getResourceAsStream("config.properties");
prop.load(input);
String col = prop.getProperty("COLLECTION_PI");
System.out.println("data is.." + col);
DBCollection collection = db.getCollection(col);
BasicDBObject obj = new BasicDBObject();
BasicDBObject fields = new BasicDBObject();
BasicDBObject fields2 = new BasicDBObject();
List<DBObject> obj1 = null;
if (User_ID != null && !User_ID.equals("") && User_ID.length() > 0) {
obj.put("User_ID", User_ID);
fields.put("_id", 0);
fields.put("User_ID", 1);
fields.put("Project_ID", 1);
fields.append("Project_Information.Project_Description", "Project_Description");
BasicDBObject fields1 = new BasicDBObject();
fields1.put("User_ID", User_ID);
}
DBCursor cursor = collection.find(obj, fields);
System.out.println("count is:" + cursor.count());
obj1 = cursor.toArray();
System.out.println("" + obj1);
cursor.close();
db.getMongo().close();
return obj1.toArray();
}
But it displays the whole structure of Project_Information.
Please specify how to achieve this. Thanks for help.
Using a 2.x MongoDB Java Driver
Here's an example using the MongoDB 2.x Java driver:
DBCollection collection = mongoClient.getDB("stackoverflow").getCollection("demo");
BasicDBObject filter = new BasicDBObject();
BasicDBObject projection = new BasicDBObject();
// project on "Project_Information.Project_Description"
projection.put("Project_Information.Project_Description", 1);
DBCursor documents = collection.find(filter, projection);
for (DBObject document : documents) {
// the response contains a sub document under the key: "Project_Information"
DBObject projectInformation = (DBObject) document.get("Project_Information");
// the "Project_Description" is in this sub document
String projectDescription = (String) projectInformation.get("Project_Description");
// prints "Sample"
System.out.println(projectDescription);
// to return this single String value in an Object[] (as implied by your OP) just do create the Object[] like this and then return it ...
Object[] r = new Object[] {projectDescription};
// prints the entire projected document e.g.
// { "_id" : { "$oid" : "59db2321811a592384865711" }, "Project_Information" : { "Project_Description" : "Sample" } }
System.out.println(document.toString());
}
Using a 3.x MongoDB Java Driver
Here's an example using the MongoDB 3.x Java driver:
// this finds all documents in a given collection (note: no parameter supplied to the find() call)
// and for each document it projects on Project_Information.Project_Description
FindIterable<Document> documents =
mongoClient.getDatabase("...").getCollection("...")
.find()
// for each attrbute you want to project you must include its dot notation path and the value 1 ...
// this is the equivalent of specifying {'Project_Information.Project_Description': 1} in the MongoDB shell
.projection(new Document("Project_Information.Project_Description", 1));
for (Document document : documents) {
// the response contains a sub document under the key: "Project_Information"
Document projectInformation = (Document) document.get("Project_Information");
// the "Project_Description" is in this sub document
String projectDescription = projectInformation.getString("Project_Description");
// prints "Sample"
System.out.println(projectDescription);
// to return this single String value in an Object[] (as implied by your OP) just do create the Object[] like this and then return it ...
Object[] r = new Object[] {projectDescription};
// prints the entire projected document e.g. { "_id" : { "$oid" : "59db2321811a592384865711" }, "Project_Information" : { "Project_Description" : "Sample" } }
System.out.println(document.toJson());
}
Java libraries won't let you directly access using dot.
They have build in getter and setter methods.
You have not mentioned which package you are using.
Here's the query that you need:
db.mycol.find({},{User_ID:1,"Project_Information.Project_Description":1})
It will give:
{ "_id" : ObjectId("59db2321811a592384865711"),
"User_ID" : "demo",
"Project_Information" : { "Project_Description" : "Sample" }
}
You will have to convert the query in whatever format your package accepts.
Here's a tutorial:
https://www.mongodb.com/blog/post/getting-started-with-mongodb-and-java-part-i
I create a MongoDB and I can put data on it, but I cannot make this structure ( I put converted db into JSON format using mongoexport):
{
"main":[
{
"name":"E",
"value":"6"
},
{
"name":"P",
"value":"1",
}
]
}
In fact I want to crate an array which contains set of paired_value of key and its value, for example a pair of "name" and the value which assigned to it.
Before I tested this code:
BasicDBObject document = new BasicDBObject();
ArrayList ar = new ArrayList();
ar.add((new BasicDBObject("name", "e")));
ar.add((new BasicDBObject("value", 6)));
document.put(ar);
Try this (untested):
BasicDBObject document = new BasicDBObject();
ArrayList ar = new ArrayList();
ar.add((new BasicDBObject("name", "e").append("value","6")));
ar.add((new BasicDBObject("name", "p").append("value","1")));
document.put("main",ar);
In the following query , I'm doing addition to a field (This field having ISO date as value) then extracting hour from that field, then group by on hour
db.campaigns.aggregate([
{$group : { _id: {$hour:{$add:['$time', 19800000]}}}}
])
Sample record of the collection
db.campaigns.findOne()
{
"_id" : ObjectId("53c7afdab92be74745af9068"),
"time" : ISODate("2013-03-08T12:25:24.973Z"),
"type" : "annoying",
"PINGS" : 143
}
The above one is working fine in Mongo shell,
I'm trying write this query in Java
Here is my partial Java code
DBObject group2Fields = new BasicDBObject();
group2Fields.put("hour", new BasicDBObject("$hour", new BasicDBObject("$add",new BasicDBObject("time",19800000))));
DBObject group2 = new BasicDBObject("_id", group2Fields);
DBObject secondGroup = new BasicDBObject("$group", group2);
I'm getting "errmsg" : "exception: field inclusion is not allowed inside of $expressions"
try this:
DBObject group2Fields = new BasicDBObject();
BasicDBList addObjects = new BasicDBList();
addObjects.add("$time");
addObjects.add(19800000);
group2Fields.put("$hour", new BasicDBObject("$add", addObjects));
DBObject group2 = new BasicDBObject("_id", group2Fields);
DBObject secondGroup = new BasicDBObject("$group", group2);
Nesting calls in your code generally helps you to "visualise" the structure that you want:
BasicDBList addArgs = new BasicDBList();
addArgs.add("$time");
addArgs.add(19800000);
DBObject group = new BasicDBObject("$group",
new BasicDBObject("_id",
new BasicDBObject("$hour",
new BasicDBObject("$add", addArgs)
)
)
);
Which of course produces a group variable that serializes like so:
{ "$group" : { "_id" : { "$hour" : { "$add" : [ "$time" , 19800000]}}}}
How do I push to a nested array in the following structure?
{
level1 : {
- arr1: [
"val1"
]
}
}
I've tried using
coll.update(entry, new BasicDBObject("$push", new BasicDBObject("level1", new BasicDBObject("arr1", "val2"))));
where coll is the collection object and entry is the entry above.
but the value is never pushed and no error is shown. What am I doing wrong?
You can reference the array in the sub-document "level1" using dot notation. So, instead of creating nested DBObjects like you've done, you simply need:
coll.update(entry, new BasicDBObject("$push", new BasicDBObject("level1.arr1", "val2")));
I wrote a test to show this works:
#Test
public void shouldPushANewValueOntoANesstedArray() throws UnknownHostException {
final MongoClient mongoClient = new MongoClient();
final DBCollection coll = mongoClient.getDB("TheDatabase").getCollection("TheCollection");
coll.drop();
//Inserting the array into the database
final BasicDBList array = new BasicDBList();
array.add("val1");
final BasicDBObject entry = new BasicDBObject("level1", new BasicDBObject("arr1", array));
coll.insert(entry);
// results in:
// { "_id" : ObjectId("51a4cfdd3004a84dde78d79c"), "level1" : { "arr1" : [ "val1" ] } }
//do the update
coll.update(entry, new BasicDBObject("$push", new BasicDBObject("level1.arr1", "val2")));
// results in:
// { "_id" : ObjectId("51a4cfdd3004a84dde78d79c"), "level1" : { "arr1" : [ "val1", "val2" ] } }
}