Android database SQLITE (used by SQLITEOPENHELPER)

 
---------------------------------------------. Java
Package com. example. sqlite;
 
 
Import android. app. Activity;
Import android. database. sqlite. SQLiteDatabase;
Import android. OS. Bundle;
Import android. view. Menu;
Import android. view. View;
Import android. view. View. OnClickListener;
Import android. widget. Button;
Import android. widget. Toast;
 
 
Public class MainActivity extends
Activity {
Button mButton1, mButton2,
MButton3;
MyDbHelper dbhelper;
SQLiteDatabase sqLiteDatabase;
 
 
Private static final int old_VERSION = 1;
Private static final int new_VERSION = 2;
 
 
@ Override
Public void onCreate (
Bundle savedInstanceState ){
Super. onCreate (savedInstanceState );
SetContentView (R. layout. activity_main );
MButton1 = (Button) findViewById (R. id. button1 );
MButton2 = (Button) findViewById (R. id. button2 );
MButton3 = (Button) findViewById (R. id. button3 );
 
 
MButton1.setOnClickListener (new OnClickListener (){
 
 
Public void onClick (View v ){
// SqLiteDatabase = openOrCreateDatabase (
// DBNAME,
// Context. MODE_PRIVATE,
// Null );
//
//
// If (sqLiteDatabase! = Null ){
//
// Toast. makeText (getBaseContext (), "created successfully" + DBNAME, 2000). show ();
//}
// Else {
// Toast. makeText (getBaseContext (), "failed to create" + DBNAME, 2000). show ();
//}
//
 
Dbhelper = new MyDbHelper (getBaseContext (), old_VERSION );
 
SqLiteDatabase = dbhelper. getWritableDatabase ();
 
Toast. makeText (getBaseContext (), "created successfully", 2000). show ();
}
});
 
MButton2.setOnClickListener (new OnClickListener (){
 
Public void onClick (View v ){
// TODO Auto-generated method stub
// SqLiteDatabase. close ();
 
 
Dbhelper = new MyDbHelper (getBaseContext (), new_VERSION );
SqLiteDatabase = dbhelper. getWritableDatabase ();
 
Toast. makeText (getBaseContext (), "updated successfully", 2000). show ();
}
});
 
// MButton3.setOnClickListener (new OnClickListener (){
//
// Public void onClick (View v ){
/// TODO Auto-generated method stub
//
// Boolean isDeleted = deleteDatabase (DBNAME );
//
// If (isDeleted ){
//
//
//
// Toast. makeText (getBaseContext (), "deleted Database" + DBNAME, 2000). show ();
//}
// Else {
// Toast. makeText (getBaseContext (), "failed to delete database" + DBNAME, 2000). show ();
//}
//}
//});
}
@ Override
Protected void onDestroy (){
// TODO Auto-generated method stub
Super. onDestroy ();
Dbhelper. close ();
}
 
 
@ Override
Public boolean onCreateOptionsMenu (
Menu menu ){
GetMenuInflater (). inflate (
R. menu. activity_main,
Menu );
Return true;
}
}
 
 
--------------------------------- MyDbHelper. java
Package com. example. sqlite;
 
 
Import android. content. Context;
Import android. database. sqlite. SQLiteDatabase;
Import android. database. sqlite. SQLiteOpenHelper;
Import android. util. Log;
 
 
Public class MyDbHelper extends SQLiteOpenHelper {
 
 
Private static final String DB_NAME = "db_2.db3 ";
Private static final String TAG = "LOOK ";
Public MyDbHelper (Context context,
 
Int version ){
Super (context, DB_NAME, null, version );
// TODO Auto-generated constructor stub
}
 
 
@ Override
Public void onCreate (
SQLiteDatabase db ){
// TODO Auto-generated method stu"
Log. d (TAG, "Begin execute onCreate ");
 
Try {
Db. beginTransaction ();
String sqlString = "create table TBL_USER (_ id integer primary key, name text not null )";
Db.exe cSQL (sqlString );
 
 
Db. setTransactionSuccessful ();
 
}
Catch (Exception e ){
// TODO: handle exception
E. printStackTrace ();
}
Finally
{
Db. endTransaction ();}
 
Log. d (TAG, "execute onCreate Completed .");
}
 
 
@ Override
Public void onUpgrade (
SQLiteDatabase db,
Int oldVersion,
Int newVersion ){
// TODO Auto-generated method stub
 
 
Log. d (TAG, "Begin execute onUpgrade ");
Try {
Db. beginTransaction ();
 
String upgradeString = "alter table TBL_USER add column created_dt timestamp not null default '2017-09-07 'collate nocase ;";
Db.exe cSQL (upgradeString );
Db. setTransactionSuccessful ();
}
Catch (Exception e ){
// TODO: handle exception
 
E. printStackTrace ();
}
Finally {
Db. endTransaction ();
}
 
 
Log. d (TAG, "execute onUpgrade Completed ");
 
}