我在SQLite浏览器中创建了一个表，并在adnroid的assets文件夹中导入数据，现在我收到错误没有这样的表，在我的logcat中，这是我的代码......
public class CardDatabase {
private static final String TB_CARD_ID="CARD_ID";
private static final String TB_CARD_QUESTION="CARD_QUESTION";
private static final String TB_CARD_ANSWER="CARD_ANSWER";
public static final String TABLE_CREATE =
"CREATE TABLE TB_CARDS (" + " CARD_ID INTEGER PRIMARY KEY, "+
" CARD_QUESTION VARCHAR ," +
" CARD_ANSWER VARCHAR);"
;
private final Context context;
public static MydataBasehelper DBHelper;
public static SQLiteDatabase db;
public CardDatabase(Context ctx)
{Log.e("problem","here2");
Log.e("info","database called");
this.context = ctx;
DBHelper = new MydataBasehelper(context);
try
{
DBHelper.createDataBase();
}
catch (IOException ioe)
{
throw new Error("Unable to create database");
}
try {
DBHelper.openDataBase();
}
catch(SQLException sqle)
{
throw sqle;
}
}
public CardDatabase open() throws SQLException {db =
DBHelper.getWritableDatabase();return this;}
public void close() {DBHelper.close();}
public static void insert(
String CARD_ID,
String CARD_QUESTION,
String CARD_ANSWER
){
ContentValues initialValues = new ContentValues();
initialValues.put(TB_CARD_ID,CARD_ID);
initialValues.put(TB_CARD_QUESTION,CARD_QUESTION);
initialValues.put(TB_CARD_ANSWER,CARD_ANSWER);
try{
Log.e("HERE IT IS", CARD_ID);
}catch (Exception e) {
Log.e("here","null");
}
db.insert("TB_CARDS", null, initialValues);
}
public static void truncate(){
db.execSQL("DELETE FROM TB_CARDS");
}
public static void deletetable(){db.execSQL("DROP TABLE IF EXISTS TB_CARDS");}
public static void createtable(){db.execSQL(TABLE_CREATE);}
public Cursor getrecord( String CARD_ID){
Log.e("we are","here");
Cursor mCursor= db.query("TB_CARDS", new String[] {
TB_CARD_ID,
TB_CARD_QUESTION,
TB_CARD_ANSWER,
},TB_CARD_ID + "=" +"'"+ CARD_ID+ "'"
,null,null,null,null,null);
if (mCursor != null) {
mCursor.moveToFirst();
}
return mCursor;
}
Cursor cur;
public Cursor selectAll(){
try{
String query="SELECT * FROM TB_CARDS";
System.out.println(query);
cur= db.rawQuery(query,null);
cur.moveToFirst();
}
catch (Exception e) {
// TODO: handle exception
e.printStackTrace();
System.out.println("problem");
}
return cur;
}
<小时/> 这是mydatabasehelper ..
public class MydataBasehelper extends SQLiteOpenHelper
{
private static final String TAG = "info";
private static final String DB_NAME = "flipdata1";
private static final String DB_PATH="data/data/cue.flip/databases/";
private SQLiteDatabase myDataBase;
private static final int DATABASE_VERSION =1332;
private Context mycontext;
public MydataBasehelper(Context context)
{
super(context, DB_NAME, null, DATABASE_VERSION);
Log.e("info","dataHelper");
}
@Override
public void onCreate(SQLiteDatabase db)
{
// Log.e("aashish","table create was called");
//db.execSQL(CardDatabase.TABLE_CREATE);
//db.execSQL(Question_database.TABLE_CREATE);
//db.execSQL(Answers_Database.TABLE_CREATE);
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion,
int newVersion)
{
Log.w(TAG, "Upgrading database from version " + oldVersion
+ " to "
+ newVersion + ", which will destroy all old data");
db.execSQL("DROP TABLE IF EXISTS " + "TB_CARDS");
//db.execSQL("DROP TABLE IF EXISTS " + Question_database.DATABASE_TABLE);
//db.execSQL("DROP TABLE IF EXISTS " + Answers_Database.DATABASE_TABLE);
onCreate(db);
}
public void createDataBase() throws IOException{
boolean dbExist = checkDataBase();
System.out.println("Create database");
if(dbExist){
System.out.println("database exists");
//do nothing - database already exist.
}else{
System.out.println("database not exists");
//By calling this method and empty database will be created into the default system path
//of your application so we are gonna be able to overwrite that database with our database.
this.getReadableDatabase();
try {
copyDataBase();
} catch (IOException e) {
throw new Error("Error copying database");
}
}
}
@Override
public synchronized void close() {
if(myDataBase != null)
myDataBase.close();
super.close();
}
private 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;
}
/**
* Copies your database from your local assets-folder to the just created empty database in the
* system folder, from where it can be accessed and handled.
* This is done by transfering bytestream.
* */
private void copyDataBase() throws IOException{
System.out.println("Copy STARTSSS");
//Open your local db as the input stream
InputStream myInput = mycontext.getAssets().open(DB_NAME);
// Path to the just created empty db
String outFileName = DB_PATH + DB_NAME;
//Open the empty db as the output stream
OutputStream myOutput = new FileOutputStream(outFileName);
//transfer bytes from the inputfile to the outputfile
byte[] buffer = new byte[1024];
int length;
while ((length = myInput.read(buffer))>0){
myOutput.write(buffer, 0, length);
}
//Close the streams
myOutput.flush();
myOutput.close();
myInput.close();
System.out.println("CopYY DONE");
}
public void openDataBase() throws SQLException{
//Open the database
System.out.println("OPEN DATABASE");
String myPath = DB_PATH + DB_NAME;
myDataBase = SQLiteDatabase.openDatabase(myPath, null, SQLiteDatabase.OPEN_READONLY);
}
}
请帮助 谢谢
答案 0 :(得分：1)
从databasehelper类的第二行ON CREATE函数中删除注释，将数据库版本更新为1333并运行。
如果第一次或多次创建数据库，每次都应该调用on-create函数！