我正在創建一個應用程序,我從不同的活動調用我的數據庫,但我不斷從事物的數據庫端獲取各種錯誤。起初,我得到一個「SQLiteException沒有這樣的數據」,當我刪除我的應用程序並安裝回來,它現在「android.database.sqlite.SQLiteConstraintException:錯誤代碼19:約束失敗」。Android數據庫問題
我不知道該做什麼了。經歷了那麼多不同的例子去了創建數據庫,但我不知道我是否失去了一些東西。這裏是我的數據庫端代碼:?
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.util.Log;
public class DBAdapter {
private static final String DATABASE_NAME = "MemoData.db";
private static final int DATABASE_VERSION = 1;
public static final String DATABASE_TABLE = "Memo";
public static final String KEY_ID = "_id";
public static final String NAME = "Title";
public static final String START_DATE = "start_date";
public static final String END_DATE = "end_date";
public static final String NOTES = "notes";
private static final String TAG = "DBAdapter";
private static final String DATABASE_CREATE = "create table Memo (_id integer primary key autoincrement,"
+ "Title text not null, start_date text not null,"
+ "end_date text not null, "
+ "notes text not null);";
private final Context context;
private DBHelper dbhelper;
private SQLiteDatabase db;
public DBAdapter(Context context) {
this.context = context;
dbhelper = new DBHelper(context);
}
private static class DBHelper extends SQLiteOpenHelper {
DBHelper(Context context){
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
@Override
public void onCreate(SQLiteDatabase db) {
db.execSQL(DATABASE_CREATE);
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
Log.w(TAG,"upgrading Database from version"+ oldVersion+ "to"
+newVersion+ "which oold data will be lost");
db.execSQL("DROP TABLE IF EXITS Memo");
onCreate(db);
}
}
public DBAdapter open()throws SQLException {
db = dbhelper.getWritableDatabase();
return this;
}
public void close(){
dbhelper.close();
}
public long createItem(String Title, String start_date,String end_date,String notes){
open();
ContentValues initialValues = new ContentValues();
initialValues.put(NAME, Title);
initialValues.put(START_DATE, start_date);
initialValues.put(END_DATE, end_date);
initialValues.put(NOTES, notes);
return db.insert(DATABASE_TABLE, null, initialValues);
}
public Cursor retrieveItems(){
SQLiteDatabase db = dbhelper.getWritableDatabase();
String[] resultColumns = new String[] {NAME,START_DATE,END_DATE,NOTES };
Cursor cursor = db.query(DATABASE_TABLE, resultColumns, null, null, null, null, null);
Integer cindex = cursor.getColumnIndex("Title");
String result = "Result = ";
if(cursor.moveToFirst()){
do {
result += cursor.getString(cindex)+ "-";
}while(cursor.moveToNext());
}
return cursor;
}
}
,這裏是主要的錯誤輸出:
08-23 22:38:17.104:錯誤/數據庫(775):插入註釋時出錯=備註:end_date =截止日期:標題=項目名稱:start_date =開始日期: 08-23 22:38:17.104:錯誤/數據庫(775):android.database.sqlite.SQLiteConstraintException:錯誤代碼19:約束失敗
08-23 22:38:17.104:錯誤/數據庫(775):at android.database.sqlite.SQL iteStatement.native_execute(本機方法)
08-23 22:38:17.104:ERROR /數據庫(775):在android.database.sqlite.SQLiteStatement.execute(SQLiteStatement.java:66)
08- 23 22:38:17.104:ERROR/Database(775):at android.database.sqlite.SQLiteDatabase.insertWithOnConflict(SQLiteDatabase.java:1313)
08-23 22:38:17.104:ERROR/Database(775) :at android.database.sqlite.SQLiteDatabase.insert(SQLiteDatabase.java:1173)
08-23 22:38:17.104:ERROR/Database(775):at com.Memo.DBAdapter.createItem(DBAdapter.java :94)
08-23 22:38:17.104:ERROR /數據庫(775):在com.Memo.NewItem.save(NewItem.java:365)
請修正此代碼塊中的雙倍間距。這是不可讀的。 – EboMike 2010-08-23 21:09:10