对不起，但我没有在网上找到任何东西。我在我的目录“资产”中使用现有的数据库。当我想更新一列时，函数返回该列已经改变，但实际上并没有发生。我试着用execSQL，但没有再次。更新现有的sqlite数据库中的列，但没有任何更改android

任何意见将不胜感激！

这里是我的DatabaseHelper代码：

public class DatabaseHelper extends SQLiteOpenHelper {

public static final String DBNAME = "program.db";

public static String DBLOCATION = "";

public static final String TableName="ProgramTable";

private Context mContext;

private SQLiteDatabase mDatabase;

public DatabaseHelper(Context context) {

super(context, DBNAME, null, 1);

this.mContext = context;

if(android.os.Build.VERSION.SDK_INT >= 17){

DBLOCATION = context.getApplicationInfo().dataDir + "/databases/";

}

else

{

DBLOCATION = "/data/data/" + context.getPackageName() + "/databases/";

}

}

@Override

public void onCreate(SQLiteDatabase db) {

}

private boolean checkDataBase()

{

File dbFile = new File(DBLOCATION + DBNAME);

return dbFile.exists();

}

//Copy the database from assets

public void copyDataBase() throws IOException

{

InputStream mInput = mContext.getAssets().open(DBNAME);

String outFileName = DBLOCATION + DBNAME;

OutputStream mOutput = new FileOutputStream(outFileName);

byte[] mBuffer = new byte[1024];

int mLength;

while ((mLength = mInput.read(mBuffer))>0)

{

mOutput.write(mBuffer, 0, mLength);

}

mOutput.flush();

mOutput.close();

mInput.close();

}

@Override

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

}

public void openDatabase() {

String dbPath = mContext.getDatabasePath(DBNAME).getPath();

if (mDatabase != null && mDatabase.isOpen()) {

return;

}

mDatabase = SQLiteDatabase.openDatabase(dbPath, null, SQLiteDatabase.OPEN_READWRITE);

}

public void closeDatabase() {

if (mDatabase != null) {

mDatabase.close();

}

}

public long Like(int id) {

ContentValues contentValues = new ContentValues();

contentValues.put("Favourite",1);

mDatabase=this.getWritableDatabase();

openDatabase();

long k=mDatabase.update(TableName, contentValues, "ID =" +Integer.valueOf(id),null);

closeDatabase();

return k;

}

public long Unlike(int id) {

ContentValues contentValues = new ContentValues();

contentValues.put("Favourite",0);

mDatabase=this.getWritableDatabase();

openDatabase();

long k =mDatabase.update(TableName, contentValues, "ID ="+Integer.valueOf(id),null);

closeDatabase();

return k;

}

}

2017-10-18

EagleJ