Question

我正在尝试做的是创建一个表，然后在其中插入一些值然后选择。我面临的问题是应用程序不幸停止。我不知道是什么问题。

我的代码是：该类调用数据库处理程序

public class SaveEvents extends Activity {
private static final String DB_NAME = "EventDB";
@Override
public void onCreate(Bundle savedInstanceState) {

    super.onCreate(savedInstanceState);
    setContentView(R.layout.edit_product);
    Bundle extras=getIntent().getExtras();
    String event=extras.getString("event");
    String date=extras.getString("date");
    String college=extras.getString("college");

    DatabaseHandler db = new DatabaseHandler(getApplicationContext());
    db.insert_data(event,date,college);
    String c=db.select_data();
    Toast.makeText(getApplicationContext(), "EventName: "+c+"", Toast.LENGTH_LONG).show();
}
}

数据库处理程序

public class DatabaseHandler extends SQLiteOpenHelper {

private static final int DATABASE_VERSION = 1;
private static final String DATABASE_NAME = "EventDB";
private static final String TABLE_NAME = "eventlist";


public DatabaseHandler(Context context) {
    super(context, DATABASE_NAME, null, DATABASE_VERSION);
}

@Override
public void onCreate(SQLiteDatabase db) {
   // Category table create query
    String CREATE_ITEM_TABLE;
    CREATE_ITEM_TABLE = "CREATE TABLE eventlist(eventname varchar(100),eventdate varchar(100),college varchar(100));";
    db.execSQL(CREATE_ITEM_TABLE);
}

@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {

}
void insert_data(String eventname,String date,String college)
{
    SQLiteDatabase db = this.getWritableDatabase();
    ContentValues values = new ContentValues();
    values.put("eventname", eventname);
    values.put("eventdate",date);
    values.put("college",college);
    db.insert(TABLE_NAME,null,values);
    db.close();
}
public String select_data()
   {
    SQLiteDatabase db = this.getWritableDatabase();
    String selectQuery = "SELECT eventname FROM eventlist where eventname='techcontest'";
    String c=null;
    Cursor cursor = db.rawQuery(selectQuery, null);
    cursor.moveToFirst();
    c=cursor.getString(0);
    return c;
}
}

我的logcat显示

03-16 20:00:19.116    8378-8378/com.example.android E/SQLiteLog﹕ (1) no     such table: eventlist
 03-16 20:00:19.122    8378-8378/com.example.android E/SQLiteDatabase﹕    Error inserting college=acs university eventdate=2-02-15 eventname=techocontest
android.database.sqlite.SQLiteException: no such table: eventlist (code 1): , while compiling: INSERT INTO eventlist(college,eventdate,eventname) VALUES (?,?,?)

Answer 1

看起来你在select_data（）方法中关闭数据库。

android数据库访问不起作用

1 个答案: