我的数据库永远不会更新

时间：2013-04-24 00:18:40

标签： java android sqlite

下面在LogCat中你可以看到我的数据库表永远不会得到更新，即使我增加了数据库版本。我在我的数据库中添加了一个表，将其导入资产文件夹。在我的onUpgrade方法中，我删除了旧版本的db并复制了新版本。至少我在我的代码中这样做。我认为这种方法永远不会被调用。我每次都没有这样的表错误。

04-24 02:08:27.502: D/szipinf(6630): Initializing inflate state
04-24 02:08:27.612: D/szipinf(6630): Initializing inflate state
04-24 02:08:27.612: D/szipinf(6630): Initializing zlib to inflate
04-24 02:08:30.972: I/Database(6630): sqlite returned: error code = 1, msg = no such table: tbl4
04-24 02:08:30.972: E/DataAdapter(6630): getTestData >>android.database.sqlite.SQLiteException: no such table: tbl4: , while compiling: SELECT * FROM tbl4  ORDER BY _ID ASC
04-24 02:08:30.982: D/AndroidRuntime(6630): Shutting down VM
04-24 02:08:30.982: W/dalvikvm(6630): threadid=1: thread exiting with uncaught exception (group=0x40018560)
04-24 02:08:31.202: E/AndroidRuntime(6630): FATAL EXCEPTION: main
04-24 02:08:31.202: E/AndroidRuntime(6630): java.lang.RuntimeException: Unable to start activity ComponentInfo{rs.androidaplikacije.themostcompleteiqtest/rs.androidaplikacije.themostcompleteiqtest.LogicTest}: android.database.sqlite.SQLiteException: no such table: tbl4: , while compiling: SELECT * FROM tbl4  ORDER BY _ID ASC
04-24 02:08:31.202: E/AndroidRuntime(6630):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1768)
04-24 02:08:31.202: E/AndroidRuntime(6630):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1784)
04-24 02:08:31.202: E/AndroidRuntime(6630):     at android.app.ActivityThread.access$1500(ActivityThread.java:123)
04-24 02:08:31.202: E/AndroidRuntime(6630):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:939)
04-24 02:08:31.202: E/AndroidRuntime(6630):     at android.os.Handler.dispatchMessage(Handler.java:99)
04-24 02:08:31.202: E/AndroidRuntime(6630):     at android.os.Looper.loop(Looper.java:130)
04-24 02:08:31.202: E/AndroidRuntime(6630):     at android.app.ActivityThread.main(ActivityThread.java:3835)
04-24 02:08:31.202: E/AndroidRuntime(6630):     at java.lang.reflect.Method.invokeNative(Native Method)
04-24 02:08:31.202: E/AndroidRuntime(6630):     at java.lang.reflect.Method.invoke(Method.java:507)
04-24 02:08:31.202: E/AndroidRuntime(6630):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:864)
04-24 02:08:31.202: E/AndroidRuntime(6630):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:622)
04-24 02:08:31.202: E/AndroidRuntime(6630):     at dalvik.system.NativeStart.main(Native Method)
04-24 02:08:31.202: E/AndroidRuntime(6630): Caused by: android.database.sqlite.SQLiteException: no such table: tbl4: , while compiling: SELECT * FROM tbl4  ORDER BY _ID ASC
04-24 02:08:31.202: E/AndroidRuntime(6630):     at android.database.sqlite.SQLiteCompiledSql.native_compile(Native Method)
04-24 02:08:31.202: E/AndroidRuntime(6630):     at android.database.sqlite.SQLiteCompiledSql.compile(SQLiteCompiledSql.java:92)
04-24 02:08:31.202: E/AndroidRuntime(6630):     at android.database.sqlite.SQLiteCompiledSql.<init>(SQLiteCompiledSql.java:65)
04-24 02:08:31.202: E/AndroidRuntime(6630):     at android.database.sqlite.SQLiteProgram.<init>(SQLiteProgram.java:83)
04-24 02:08:31.202: E/AndroidRuntime(6630):     at android.database.sqlite.SQLiteQuery.<init>(SQLiteQuery.java:49)
04-24 02:08:31.202: E/AndroidRuntime(6630):     at android.database.sqlite.SQLiteDirectCursorDriver.query(SQLiteDirectCursorDriver.java:42)
04-24 02:08:31.202: E/AndroidRuntime(6630):     at android.database.sqlite.SQLiteDatabase.rawQueryWithFactory(SQLiteDatabase.java:1356)
04-24 02:08:31.202: E/AndroidRuntime(6630):     at android.database.sqlite.SQLiteDatabase.rawQuery(SQLiteDatabase.java:1324)
04-24 02:08:31.202: E/AndroidRuntime(6630):     at rs.androidaplikacije.themostcompleteiqtest.TestAdapter.getTestDataLogic(TestAdapter.java:103)
04-24 02:08:31.202: E/AndroidRuntime(6630):     at rs.androidaplikacije.themostcompleteiqtest.LogicTest.nextQuestion(LogicTest.java:136)
04-24 02:08:31.202: E/AndroidRuntime(6630):     at rs.androidaplikacije.themostcompleteiqtest.LogicTest.onCreate(LogicTest.java:93)
04-24 02:08:31.202: E/AndroidRuntime(6630):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
04-24 02:08:31.202: E/AndroidRuntime(6630):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1722)
04-24 02:08:31.202: E/AndroidRuntime(6630):     ... 11 more
04-24 02:08:32.912: I/Process(6630): Sending signal. PID: 6630 SIG: 9

数据库助手：

public class DataBaseHelper extends SQLiteOpenHelper
{
private static String TAG = "DataBaseHelper"; // Tag just for the LogCat window
//destination path (location) of our database on device
private static String DB_PATH = "/data/data/rs.androidaplikacije.themostcompleteiqtest/databases/"; 
private static String DB_NAME ="pitanja.sqlite";// Database name
private static SQLiteDatabase mDataBase; 
private final Context mContext;
private static final int DATABASE_VERSION = 25;

public DataBaseHelper(Context mojContext) 
{
    super(mojContext, DB_NAME, null, DATABASE_VERSION);// 1 it's Database Version
    DB_PATH = mojContext.getApplicationInfo().dataDir + "/databases/";
    this.mContext = mojContext;
}

public void createDataBase() throws IOException
{
    //If database not exists copy it from the assets


        this.getReadableDatabase();
        this.close();
        try 
        {
            //Copy the database from assests
            copyDataBase();
            Log.e(TAG, "createDatabase database created");
        } 
        catch (IOException mIOException) 
        {
            throw new Error("ErrorCopyingDataBase");
        }
    }

/**
 * Check if the database already exist to avoid re-copying the file each time you open the application.
 * @return true if it exists, false if it doesn't
 */
public boolean checkDataBase(){

SQLiteDatabase checkDB = null;

try{
String myPath = DB_PATH + DB_NAME;
checkDB = SQLiteDatabase.openDatabase(myPath, null, SQLiteDatabase.OPEN_READONLY);

}catch(SQLiteException e){

//database does't exist yet.

}

if(checkDB != null){

checkDB.close();

}

return checkDB != null ? true : false;
}
    /*Check that the database exists here: /data/data/your package/databases/Da Name
    private boolean checkDataBase()
    {
        File dbFile = new File(DB_PATH + DB_NAME);
        //Log.v("dbFile", dbFile + "   "+ dbFile.exists());
        return dbFile.exists();
    }*/


    //Copy the database from assets
    private void copyDataBase() throws IOException
    {
        InputStream mInput = mContext.getAssets().open(DB_NAME);
        String outFileName = DB_PATH + DB_NAME;
        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();
    }

    //Open the database, so we can query it
    public boolean openDataBase() throws SQLException
    {
        String mPath = DB_PATH + DB_NAME;
        //Log.v("mPath", mPath);
        mDataBase = SQLiteDatabase.openDatabase(mPath, null, SQLiteDatabase.CREATE_IF_NECESSARY);
        //mDataBase = SQLiteDatabase.openDatabase(mPath, null, SQLiteDatabase.NO_LOCALIZED_COLLATORS);
        return mDataBase != null;
    }
    @Override
    public void close() 
    {
        if(mDataBase != null)
            mDataBase.close();
        super.close();
    }

    @Override
    public void onCreate(SQLiteDatabase arg0) {
        }

    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
         mContext.deleteDatabase(DB_NAME);
         try {
            copyDataBase();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        }
    }

适配器：

public class TestAdapter 
{
    protected static final String TAG = "DataAdapter";

    private final Context mContext;
    private SQLiteDatabase mDb;
    private DataBaseHelper mDbHelper;

    public TestAdapter(Context context) 
    {
        this.mContext = context;
        mDbHelper = new DataBaseHelper(mContext);
    }

    public TestAdapter createDatabase() throws SQLException 
    {
        try 
        {
            mDbHelper.createDataBase();
        } 
        catch (IOException mIOException) 
        {
            Log.e(TAG, mIOException.toString() + "  UnableToCreateDatabase");
            throw new Error("UnableToCreateDatabase");
        }
        return this;
    }

    public TestAdapter open() throws SQLException 
    {
        try 
        {
            mDbHelper.openDataBase();
            mDbHelper.close();
            mDb = mDbHelper.getReadableDatabase();
        } 
        catch (SQLException mSQLException) 
        {
            Log.e(TAG, "open >>"+ mSQLException.toString());
            throw mSQLException;
        }
        return this;
    }

    public void close() 
    {
        mDbHelper.close();
    }

     public Cursor getTestDataMDPI(String whereClause)
     {;
         try
         {
             String sql ="SELECT * FROM tblPitanjaDanskaMDPI WHERE 1 = 1 " + whereClause + " ORDER BY _ID ASC";

             Cursor mCur = mDb.rawQuery(sql, null);
             if (mCur!=null)
             {
                mCur.moveToNext();
             }
             return mCur;
         }
         catch (SQLException mSQLException) 
         {
             Log.e(TAG, "getTestData >>"+ mSQLException.toString());
             throw mSQLException;
         }
     }
     public Cursor getTestDataHDPI(String whereClause)
     {;
         try
         {
             String sql ="SELECT * FROM tblPitanjaDanskaHDPI WHERE 1 = 1 " + whereClause + " ORDER BY _ID ASC";

             Cursor mCur = mDb.rawQuery(sql, null);
             if (mCur!=null)
             {
                mCur.moveToNext();
             }
             return mCur;
         }
         catch (SQLException mSQLException) 
         {
             Log.e(TAG, "getTestData >>"+ mSQLException.toString());
             throw mSQLException;
         }
     }
     public Cursor getTestDataLogic(String whereClause)
     {;
         try
         {
             String sql ="SELECT * FROM tbl4 " + whereClause + " ORDER BY _ID ASC";

             Cursor mCur = mDb.rawQuery(sql, null);
             if (mCur!=null)
             {
                mCur.moveToNext();
             }
             return mCur;
         }
         catch (SQLException mSQLException) 
         {
             Log.e(TAG, "getTestData >>"+ mSQLException.toString());
             throw mSQLException;
         }
     }
}

这里只是让你们看到这个表存在（它是一个工作表，只是为了尝试这个onUpgrade方法）：

enter image description here

1 个答案:

答案 0 :(得分：0)

啊，您的用法实际上是完全错误的：您无法删除数据库文件，并且期望任何数据库句柄仍然有效。删除文件后，SQLiteDatabase db实例不再有效：我很惊讶你甚至没有崩溃。

如果不进行严格的扭曲以确保重置所有数据库句柄，您的技术（删除文件并复制新文件）将无法正常工作：如果您想使用onUpgrade您想要做的是或者进行一对DROP TABLE / CREATE TABLE来电或ALTER TABLE来电，以应用您的更改。

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