連線資料庫SQLite修改一筆資料，方法1：SQL語法: Update


注意：整個事件程式碼都必須放在
onCreate() 
{  
}
下面
   // Button元件的事件處理 - 修改記錄
    public void button1_Click(View view) {
    	//Update 資料表名稱 set name = ‘jack’, chi = 90 where id_no=’90001’
    	//db.execSQL("Update 資料表名稱 set name = 'jack', chi = 90 where id_no='90001'");
    	db.execSQL("Update " + DATABASE_TABLE + " set 文字欄位2 = '" + ed2.getText().toString() + "', 實數欄位3=" + ed3.getText().toString() + " where 文字欄位1='" + ed1.getText().toString() + "'");
        output.setText("更新記錄成功: ");     
    } 

..........................

範例：

import android.view.*;
import android.widget.*;
import android.content.ContentValues;
import android.database.Cursor;

import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;


public class MainActivity extends Activity {

    private SQLiteDatabase db;
    private MyDBHelper dbHelper;
    private static String DATABASE_TABLE = "資料表名稱";'

    private EditText ed1,ed2,ed3;
    private TextView output;
 

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
			
	 // 建立SQLiteOpenHelper物件
        dbHelper = new MyDBHelper(this);
        db = dbHelper.getWritableDatabase(); // 開啟資料庫
        // 取得TextView元件
        output = (TextView) findViewById(R.id.textView4);  	
		
    }//end of onCreate()


   // Button元件的事件處理 - 修改記錄
    public void button1_Click(View view) {
    	//Update 資料表名稱 set name = ‘jack’, chi = 90 where id_no=’90001’
    	//db.execSQL("Update 資料表名稱 set name = 'jack', chi = 90 where id_no='90001'");
    	db.execSQL("Update " + DATABASE_TABLE + " set 文字欄位2 = '" + ed2.getText().toString() + "', 實數欄位3=" + ed3.getText().toString() + " where 文字欄位1='" + ed1.getText().toString() + "'");
        output.setText("更新記錄成功: ");     
    } 
	
//連線資料庫SQLite，新增資料表	
	public class MyDBHelper extends SQLiteOpenHelper {
		private static final String DATABASE_NAME = "資料庫名稱";
		private static final int DATABASE_VERSION = 1;
		
		public MyDBHelper(Context context) {
			super(context, DATABASE_NAME, null, DATABASE_VERSION);
		}
		@Override
		public void onCreate(SQLiteDatabase db) {			
			//新增資料表
			//資料表名稱與欄位名稱，不要用中文名稱
			db.execSQL("CREATE TABLE " + DATABASE_TABLE + " (_id integer primary key autoincrement, "
			           + "name text no null, price real no null, num real no null)");
		}
		@Override
		public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
			db.execSQL("DROP TABLE IF EXISTS " + DATABASE_TABLE );
	        onCreate(db);
		}
	} //end of MyDBHelper extends SQLiteOpenHelper ()