How to Create DataBase in Android

Create a new project in Android Studio

File – New Android Project

Using of DataBaseHelper Class

Once the projected is created create a new class in your project src directory and name it as DataBaseHendler.java(Right click on src/package – New – Class)

Now extend your DatabaseHandler.java class from SQLiteOpenHelper.

public class DataBaseHendler extends SqLiteOpenHelper {

After extends your class from SqLiteOpenHelper you need to override two method onCreate() and onUpgrade.

onCreate():-These is where we need to write create table statements. This is called when database is created.

onUpgrade():-This method is called when database is upgraded like modifying the table structure, adding constraints to database .

Create DataBaseHelper Class
Right click on package Name – New – Java Class

For Ex:-

[code lang=”js”]
public class DataBaseHelper extends SQLiteOpenHelper {
// Database version name
private static final int DATABASE_VERSION = 1;
// Database name
private static final String DATBASE_NAME = "regForm.db";

public static final String TABLE_NAME = "user";
public static final String USER_ID = "_id";
public static final String NAME = "name";
public static final String EMAIL = "email";

public DataBaseHelper(Context context) {
super(context, DATBASE_NAME, null, DATABASE_VERSION);
}

//Creating Tables
@Override
public void onCreate(SQLiteDatabase db) {
String CREATE_USER_TABLE = "create table " + TABLE_NAME
+ " ( " + USER_ID + " integer primary key autoincrement,"
+ NAME + " TEXT,"
+ EMAIL + " TEXT,"
db.execSQL(CREATE_USER_TABLE); }
// Upgrading database
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {

}
}

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Inserting new Record in the Table

To Insert a new Record in Table we need to create an Object of ContentValues class and put the Values in this like:

[code lang=”js”]
// Assign value for each row
ContentValues values = new ContentValues();
values.put(KEY_NAME, contact.getName()); // Contact Name
values.put(KEY_PH_NO, contact.getAddress()); // Contact Address
// Insert the row into your table
db.insert(TABLE_CONTACTS, null, values);
db.close(); // Closing database connection
}
[/code]

Reading Row

For Ex:

Deleting Record

[code lang=”js”]
deleteContact() will delete single contact from database.
deleteContact()
public void deleteContact(Contact contact){
SqLiteDatabase db=this.getWriteableDatabase();
Db.delete(TABLE_CONTACTS, KEY_ID + “ ?”, new String [] { String.valueof(contact.getid)});
Db.close();
}
[/code]