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In this mongoDB tutorial we will write java programs to FIND documents where field is (less than) using lt and lte operator in Collection In MongoDb in java.

Contents of page >

1) Program to Query Document From Collection In MongoDb in java using lt and lte Operators >

1.1) Program to Query Document From Collection In MongoDb in java using lt (less than) Operator >
1.2) Program to Query Document From Collection In MongoDb in java using lte (less than equal) Operator >

1) Program to Query Document From Collection In MongoDb in java using lt and lte Operators >

1.1) Program to Query Document From Collection In MongoDb in java using lt (less than) Operator >

FIND documents where id < 2

package queryDocumentFromCollectionInMongoDb;

/**

* Write a program to Query Document From Collection In MongoDb in java using Lt And Lte Operator

import com.mongodb.BasicDBObject;

import com.mongodb.DB;

import com.mongodb.DBCollection;

import com.mongodb.DBCursor;

import com.mongodb.MongoClient;

import com.mongodb.MongoClientURI;

import com.mongodb.WriteResult;

public class QueryDocumentFromCollectionInMongoDb5_usingLtAndLteOperator {

public static void main(String[] args) {

/* Connect to MongoDB */

MongoClient mongoClient =

new MongoClient(new MongoClientURI("mongodb://localhost:27017"));

/* Connect to DATABASE */

//If in case database doesn't exists, it will be created at runtime

DB db = mongoClient.getDB("mydb");

/* Get the COLLECTION (TABLE) */

//If in case collection (Table) doesn't exists, it will be created at runtime

DBCollection dbCollection = db.getCollection("Employee");

/*If collection already exists, you may remove everything

from collection for perfect OUTPUT of program*/

dbCollection.remove(new BasicDBObject()); //Not Mandatory

/* create a BasicDBObject1 (document /record) */

BasicDBObject basicDBObject1 = new BasicDBObject();

basicDBObject1.put("id", 1);

basicDBObject1.put("name", "Ankit");

/* Insert document1/record1 in COLLECTION in MongoDB */

System.out.println("Insert document1");

dbCollection.insert(basicDBObject1);

/* create a BasicDBObject2 (document /record) */

BasicDBObject basicDBObject2 = new BasicDBObject();

basicDBObject2.put("id", 2);

basicDBObject2.put("name", "Sam");

/* Insert document2 in collection in MongoDB */

System.out.println("Insert document2");

dbCollection.insert(basicDBObject2);

/* create a BasicDBObject3 (document /record) */

BasicDBObject basicDBObject3 = new BasicDBObject();

basicDBObject3.put("id", 3);

basicDBObject3.put("name", "Neh");

/* Insert document3 in collection in MongoDB */

System.out.println("Insert document3");

dbCollection.insert(basicDBObject3);

/* Display documents of collection before QUERING DOCUMENTs in MongoDB */

System.out.println("\nDisplay collection "

+ "before QUERING collection in MongoDB");

DBCursor cursor0 = dbCollection.find();

while (cursor0.hasNext()) {

System.out.println(cursor0.next());

}

/** At this stage dbCollection looks like this >

{ "_id" : { "$oid" : "58559179ad8dc831e8df7a3e"} , "id" : 1 , "name" : "Ankit"}

{ "_id" : { "$oid" : "58559179ad8dc831e8df7a3f"} , "id" : 2 , "name" : "Sam"}

{ "_id" : { "$oid" : "58559179ad8dc831e8df7a40"} , "id" : 3 , "name" : "Neh"}

/** Now, let's FIND the documents from collection in MongoDB */

/** FIND documents where id < 2 */

BasicDBObject basicDBObject_SearchCondition = new BasicDBObject();

//$lt operator is for LESS THAN

//Pass > $lt as key > and > 2 as value

basicDBObject_SearchCondition.put("id",

new BasicDBObject("$lt", 2));

/** Execute FIND/SEARCH query - To FIND DOCUMENT in MongoDB */

//find method Select documents in collection and returns cursor to the selected documents.

System.out.println("\nExecute FIND query where id < 2 ");

DBCursor cursor = dbCollection.find(basicDBObject_SearchCondition);

/* Display documents of collection after QUERING collection in MongoDB */

System.out.println("\nDisplay documents of collection "

+ "after QUERING collection in MongoDB ");

while (cursor.hasNext()) {

System.out.println(cursor.next());

}

/** At this stage dbCollection looks like this >

{ "_id" : { "$oid" : "58559179ad8dc831e8df7a3e"} , "id" : 1 , "name" : "Ankit"}

}

/* OUTPUT

Insert document1

Insert document2

Insert document3

Display collection before QUERING collection in MongoDB

{ "_id" : { "$oid" : "58559179ad8dc831e8df7a3e"} , "id" : 1 , "name" : "Ankit"}

{ "_id" : { "$oid" : "58559179ad8dc831e8df7a3f"} , "id" : 2 , "name" : "Sam"}

{ "_id" : { "$oid" : "58559179ad8dc831e8df7a40"} , "id" : 3 , "name" : "Neh"}

Execute FIND query where id < 2

Display documents of collection after QUERING collection in MongoDB

{ "_id" : { "$oid" : "58559179ad8dc831e8df7a3e"} , "id" : 1 , "name" : "Ankit"}

1.2) Program to Query Document From Collection In MongoDb in java using lte (less than equal) Operator >

FIND documents where id <= 2

FIND documents where id <= 2 From this collection

{ "_id" : { "$oid" : "58559179ad8dc831e8df7a3e"} , "id" : 1 , "name" : "Ankit"}

{ "_id" : { "$oid" : "58559179ad8dc831e8df7a3f"} , "id" : 2 , "name" : "Sam"}

{ "_id" : { "$oid" : "58559179ad8dc831e8df7a40"} , "id" : 3 , "name" : "Neh"}

BasicDBObject basicDBObject_SearchCondition = new BasicDBObject();

//$lte operator is for LESS THAN EQUAL

//Pass > $lte as key - and - 2 as value

basicDBObject_SearchCondition.put("id", new BasicDBObject("$lte", 2));

Result

{ "_id" : { "$oid" : "58559179ad8dc831e8df7a3e"} , "id" : 1 , "name" : "Ankit"}

{ "_id" : { "$oid" : "58559179ad8dc831e8df7a3f"} , "id" : 2 , "name" : "Sam"}

Download >

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OR

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