Check for Duplicates in an Array in MongoDB

AmitDiwan
Updated on 01-Jul-2020 06:46:00

1K+ Views

To check for duplicates in an array, use aggregate() in MongoDB. Let us create a collection with documents −> db.demo756.insertOne({"SubjectName":["MySQL", "MongoDB", "Java"]}); {    "acknowledged" : true,    "insertedId" : ObjectId("5eb01e0d5637cd592b2a4add") } > db.demo756.insertOne({"SubjectName":["MongoDB", "MySQL", "MongoDB", "C", "C+", "MySQL"]}); {    "acknowledged" : true,    "insertedId" : ObjectId("5eb01e2b5637cd592b2a4ade") }Display all documents from a collection with the help of find() method −> db.demo756.find();This will produce the following output −{ "_id" : ObjectId("5eb01e0d5637cd592b2a4add"), "SubjectName" : [ "MySQL", "MongoDB", "Java" ] } { "_id" : ObjectId("5eb01e2b5637cd592b2a4ade"), "SubjectName" : [ "MongoDB", "MySQL", "MongoDB", "C", "C+", "MySQL" ] }Following is the query to check for ... Read More

Sort MongoDB Field Containing Both Integer and Decimal Values

AmitDiwan
Updated on 01-Jul-2020 06:42:25

396 Views

To sort, use sort() in MongoDB. Let us create a collection with documents −> db.demo755.insertOne({"Value":10}); {    "acknowledged" : true,    "insertedId" : ObjectId("5eae9e72a930c785c834e572") } > db.demo755.insertOne({"Value":10.5}); {    "acknowledged" : true,    "insertedId" : ObjectId("5eae9e75a930c785c834e573") } > db.demo755.insertOne({"Value":9.5}); {    "acknowledged" : true,    "insertedId" : ObjectId("5eae9e79a930c785c834e574") } > db.demo755.insertOne({"Value":12.5}); {    "acknowledged" : true,    "insertedId" : ObjectId("5eae9e7fa930c785c834e575") } > db.demo755.insertOne({"Value":11.5}); {    "acknowledged" : true,    "insertedId" : ObjectId("5eae9e87a930c785c834e576") } > db.demo755.insertOne({"Value":6}); {    "acknowledged" : true,    "insertedId" : ObjectId("5eae9e97a930c785c834e577") }Display all documents from a collection with the help of find() method −> db.demo755.find();This will produce ... Read More

Convert Birth Date Records to Age with MongoDB

AmitDiwan
Updated on 01-Jul-2020 06:41:02

2K+ Views

Let us create a collection with documents −> db.demo754.insertOne({"DateOfBirth":new Date("2000-05-03")}); {    "acknowledged" : true,    "insertedId" : ObjectId("5eae9b2da930c785c834e56f") } > db.demo754.insertOne({"DateOfBirth":new Date("2010-01-21")}); {    "acknowledged" : true,    "insertedId" : ObjectId("5eae9b34a930c785c834e570") } > db.demo754.insertOne({"DateOfBirth":new Date("2018-05-03")}); {    "acknowledged" : true,    "insertedId" : ObjectId("5eae9b3da930c785c834e571") }Display all documents from a collection with the help of find() method −> db.demo754.find();This will produce the following output −{ "_id" : ObjectId("5eae9b2da930c785c834e56f"), "DateOfBirth" : ISODate("2000-05-03T00:00:00Z") } { "_id" : ObjectId("5eae9b34a930c785c834e570"), "DateOfBirth" : ISODate("2010-01-21T00:00:00Z") } { "_id" : ObjectId("5eae9b3da930c785c834e571"), "DateOfBirth" : ISODate("2018-05-03T00:00:00Z") }Following is the query to convert date of birth to age −> db.demo754.aggregate( ... Read More

Importance of the parseBoolean Method in Java

raja
Updated on 01-Jul-2020 06:13:23

187 Views

The parseBoolean() method is an important method of a Boolean class. The parseBoolean() is a static method and can parse the String method argument into a Boolean object. The parseBoolean() method of Boolean class returns the boolean represented by the string argument.Syntaxpublic static boolean parseBoolean(String s)Exampleimport java.util.Scanner; public class ParseBooleanMethodTest {    public static void main(String[] args) {       System.out.print("Are you ready to play cricket(true/false)?");       Scanner scanner = new Scanner(System.in);       String str = scanner.nextLine();       scanner.close();       // Convert the user input into boolean       boolean answer ... Read More

Use SearchView in Android

Azhar
Updated on 01-Jul-2020 06:10:17

2K+ Views

This example demonstrates how do I use SearchView in android.Step 1 − Create a new project in Android Studio, go to File ⇒ New Project and fill all required details to create a new projectStep 2 − Add the following code to res/layout/activity_main.xml.         Step 3 − Add the following code to src/MainActivity.javaimport android.support.v7.app.AppCompatActivity; import android.os.Bundle; import android.widget.ArrayAdapter; import android.widget.ListView; import android.widget.SearchView; import android.widget.Toast; import java.util.ArrayList; public class MainActivity extends AppCompatActivity {    SearchView searchView;    ListView listView;    ArrayList list;    ArrayAdapter adapter;    @Override    protected void onCreate(Bundle savedInstanceState) {       super.onCreate(savedInstanceState); ... Read More

Use ViewFlipper in Android

Azhar
Updated on 01-Jul-2020 06:09:31

743 Views

This example demonstrates how do I use viewFlipper in android.Step 1 − Create a new project in Android Studio, go to File ⇒ New Project and fill all required details to create a new project.Step 2 − Add the following code to res/layout/activity_main.xml.                             Step 3 − Add the following code to src/MainActivity.javaimport android.support.v7.app.AppCompatActivity; import android.os.Bundle; import android.view.Gravity; import android.view.View; import android.widget.TextView; import android.widget.ViewFlipper; public class MainActivity extends AppCompatActivity {    private ViewFlipper viewFlipper;    @Override    protected void onCreate(Bundle savedInstanceState) {     ... Read More

Restart an Activity in Android

Azhar
Updated on 01-Jul-2020 06:08:07

3K+ Views

This example demonstrates how do I restart an Activity in android.Step 1 − Create a new project in Android Studio, go to File ⇒ New Project and fill all required details to create a new project.Step 2 − Add the following code to res/layout/activity_main.xml.         Step 3 − Add the following code to src/MainActivity.javaimport android.content.Intent; import android.support.v7.app.AppCompatActivity; import android.os.Bundle; import android.view.View; import android.widget.Button; import android.widget.TextView; import java.util.Random; public class MainActivity extends AppCompatActivity {    TextView textView;    Button button;    Random random = new Random();    @Override    protected void onCreate(Bundle savedInstanceState) {       ... Read More

Calculate Bitonicity of an Array

sudhir sharma
Updated on 01-Jul-2020 06:07:18

125 Views

The bitonicity of an array is defined using the following syntax −To find bitonicity of an array based on its elements is −Bitonicity = 0 , initially arr[0] i from 0 to n Bitonicity = Bitonicity+1 ; if arr[i] > arr[i-1] Bitonicity = Bitonicity-1 ; if arr[i] < arr[i-1] Bitonicity = Bitonicity ; if arr[i] = arr[i-1]ExampleThe code for finding the bitonicity of an array we have used a variable called bitonicity, that changes its based on the comparison of the current and previous elements of the array. The above logic updates the bitonicity of the array and final bitonicity ... Read More

Add Shadow on Text in Android

Azhar
Updated on 01-Jul-2020 06:05:41

298 Views

This example demonstrates how do I add shadow on a text in android.Step 1 − Create a new project in Android Studio, go to File ⇒ New Project and fill all required details to create a new project.Step 2 − Add the following code to res/layout/activity_main.xml.     Step 3 − Add the following code to src/MainActivity.javaimport android.graphics.Color; import android.support.v7.app.AppCompatActivity; import android.os.Bundle; import android.widget.TextView; public class MainActivity extends AppCompatActivity {    @Override    protected void onCreate(Bundle savedInstanceState) {       super.onCreate(savedInstanceState);       setContentView(R.layout.activity_main);       TextView textView = findViewById(R.id.textView);       textView.setTextColor(Color.MAGENTA);     ... Read More

Play Audio File from Assets Directory in Android

Azhar
Updated on 01-Jul-2020 06:03:41

3K+ Views

This example demonstrates how do I play audio file from the assets directory in android.Step 1 − Create a new project in Android Studio, go to File ⇒ New Project and fill all required details to create a new project.Step 2 − Add the following code to res/layout/activity_main.xml.     Step 3 − Create a asset folder, Right click on the project → New → Folder → Asset Folder.Copy and paste the audio file into the assets folder.Step 4 − Add the following code to src/MainActivity.javaimport android.content.res.AssetFileDescriptor; import android.media.MediaPlayer; import android.support.v7.app.AppCompatActivity; import android.os.Bundle; import android.view.View; import android.widget.Button; import android.widget.Toast; ... Read More

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