SQLiteReadOnlyDatabaseException：尝试写入只读数据库 [英] SQLiteReadOnlyDatabaseException: attempt to write a readonly database
问题描述
只是改变了我的数据是硬code到数据库中使用SQLite数据库浏览器。之前，我改变了我所有的查询工作正常，但是当我更改时发生错误。我不能做那些查询了。该数据库只能读不能写。我想，当顾客点餐到表条例，但未能插入一个条目。我的数据库文件是在资产/ Restaurantdb.sql
Just changed my data that are hard-code into database to using SQLite Database Browser. Before I changed all my query works fine but errors occurs when I changed. I can't do those query anymore. The database can only read but not write. I was trying to insert an entry when customer order food into table "Bill" but failed. my database file is at assets/Restaurantdb.sql
还有一个奇怪的发现是，我卸载了整个事情，改变我的食物表（如汉堡到Burger1），它显示出汉堡，而不是Burger1。一些食品名称
One more strange discovery is that I uninstall the whole thing and change some food name in my "FOOD"table (like Burger to Burger1), it show Burger instead of Burger1.
+++++++++++++++++++++++++++++++++++++++++++++++ ++++++++++++++++++++++++++++++++++ 这是我最新code，但它endup得到这个新的错误。在资产的文件夹我的数据库文件名为Restaurantdb。 错误：当检索食品名称没有这样的一桌菜。 ++++++++++++++++++++++++++++++++++++++++++++++++++ +++++++++++++++++++++++++++++++
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ This is my lastest code but it endup got this new error. My database file in assets folder named "Restaurantdb. Error: No such table Food when retrieve name from food. +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
package com.restaurant.sesame;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
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.SQLiteException;
import android.database.sqlite.SQLiteOpenHelper;
import android.util.Log;
import android.widget.Toast;
public class Restaurant {
public static final String KEY_ROWID = "_id";
public static final String KEY_NAME = "name";
public static final String KEY_DETAIL = "detail";
public static final String KEY_PRICE = "price";
private static String DATABASE_NAME ="Restaurantdb";
private static String DATABASE_TABLE ="Food";
private static final int DATABASE_VERSION = 1;
private static String DB_PATH = "/data/data/com.restaurant.sesame/databases/";
private static SQLiteDatabase ourDatabase;
private static Context myContext;
private DBHelper ourHelper;
private static class DBHelper extends SQLiteOpenHelper{
public DBHelper(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
public void createDataBase() throws IOException{
boolean dbExist = checkDataBase();
if(dbExist){
//do nothing - database already exist
}else{
//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");
}
}
}
/**
* 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
*/
private boolean checkDataBase(){
SQLiteDatabase checkDB = null;
try{
String myPath = DB_PATH + DATABASE_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{
//Open your local db as the input stream
InputStream myInput = myContext.getAssets().open(DATABASE_NAME);
// Path to the just created empty db
String outFileName = DB_PATH + DATABASE_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();
}
public void openDataBase() throws SQLException{
//Open the database
String myPath = DB_PATH + DATABASE_NAME;
ourDatabase = SQLiteDatabase.openDatabase(myPath, null, SQLiteDatabase.OPEN_READONLY);
}
@Override
public synchronized void close() {
if(ourDatabase != null)
ourDatabase.close();
super.close();
}
@Override
public void onCreate(SQLiteDatabase db) {
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
}
}
public Restaurant(Context c)
{
myContext = c;
DBHelper helper = new DBHelper (myContext);
this.ourDatabase = helper.getWritableDatabase();
}
public Restaurant open() throws SQLException
{
ourHelper = new DBHelper (myContext);
try {
ourHelper.createDataBase();
} catch (IOException ioe) {
throw new Error("Unable to create database");
}
try {
ourHelper.openDataBase();
}catch(SQLException sqle){
throw sqle;
}
return this;
}
public void close()
{
ourHelper.close();
}
public String[] getWantedInfos(String KEY_WANTED){
String[]columns = new String[]{KEY_WANTED};
Cursor c = ourDatabase.query(DATABASE_TABLE, columns, null, null, null, null, null);
String [] wanted = new String[c.getCount()] ;
int i = 0,
iWanted = c.getColumnIndex(KEY_WANTED);
for(c.moveToFirst();!c.isAfterLast();c.moveToNext())
{
wanted[i] = c.getString(iWanted);
++i;
}
return wanted;
}
public String getOneInfo(String id, String info)
{
Log.w("my app", "IN getOneInfo TOP!!!!");
String [] columns = new String [] {id,info};
Cursor c = ourDatabase.query(DATABASE_TABLE, columns, KEY_ROWID + " = "+ id, null, null, null, null);
Log.w("getOneInfo", "IN getOneInfo after query!!!!");
String result ="";
int iRow = c.getColumnIndex(id);
int iInfo = c.getColumnIndex(info);
if(c!=null){
c.moveToFirst();
result =c.getString(iInfo);
return result;
}
return null;
}
public String getBillInfo(String name, String info)
{
Log.w("getBillInfo", "IN getBillInfo TOP!!!!");
String [] columns = new String [] {KEY_NAME,info};
Log.w("getBillInfo ","pass in"+ name);
Log.w("getBillInfo", "pass in"+info);
Cursor c = ourDatabase.query("Bill", columns, "name = '"+ name+ "'", null, null, null, null);
Log.w("getBillInfo", "IN getBillInfo after query!!!!");
String result ="";
int iInfo = c.getColumnIndex(info);
Log.w("getBillInfo", "IN getBillInfo before loop!!!!");
for(c.moveToFirst();!c.isAfterLast();c.moveToNext())
{
Log.w("getBillInfo", "IN getBillInfo inside loop!!!!");
c.moveToFirst();
result =c.getString(iInfo);
Log.w("getBillInfo", "IN getBillInfo XXXXnull!!!!");
Log.w("getBillInfo", "quantity in bill is ==>"+result);
return result;
}
Log.w("getBillInfo", "IN getBillInfo null!!!!");
return "0";
}
public String getBillTotal()
{
Log.w("Bill Total", "YYYY33333");
Cursor c = ourDatabase.rawQuery(
"SELECT SUM(total)as total FROM Bill", null);
Log.w("Bill Total", "YYYY4444");
String result ="";
int iInfo = c.getColumnIndex("total");
Log.w("Bill Total", "YYYY5555");
if(c!=null){
c.moveToFirst();
result =c.getString(iInfo);
return result;
}
return "0.00";
}
public String getBillData()
{
Log.w("my app", "IN getData TOP!!!!");
String [] columns = new String [] {"_id","name","price","quantity","total"};
Cursor c = ourDatabase.query("Bill", columns, null, null, "name", null, null);
String result ="";
int iRow = c.getColumnIndex("_id");
int iName = c.getColumnIndex("name");
int iPrice = c.getColumnIndex("price");
int iQuantity = c.getColumnIndex("quantity");
int iTotal = c.getColumnIndex("total");
Log.w("my app", "IN getData MIDDLE!!!!");
int i = 1;
for(c.moveToFirst();!c.isAfterLast();c.moveToNext())
{
result = result + Integer.toString(i)+"\t" +
c.getString(iName) + "\t" +
c.getString(iPrice) +"\t" +
c.getString(iQuantity) + "\t" +
c.getString(iTotal) + "\n";
i++;
}
Log.w("my app", "IN getData END!!!!");
return result;
}
public long createOrderEntry(int id, int quantityItem)
{
String [] columns = new String [] {KEY_ROWID,KEY_NAME,KEY_PRICE};
Cursor c = ourDatabase.query(DATABASE_TABLE, columns, KEY_ROWID + "=" + Integer.toString(id) , null, null, null, null);
if(c!= null)
{
ContentValues cv = new ContentValues();
c.moveToFirst();
String nameItem = c.getString(1);
double priceItem = c.getDouble(2);
double totalItem = priceItem *quantityItem;
cv.put("name", nameItem);
cv.put("price", priceItem);
cv.put("quantity", quantityItem);
cv.put("total", totalItem);
return ourDatabase.insert("Bill", null, cv);
}
return 0;
}
public boolean deleteOrderEntry(int lRow)
{
String [] columns = new String [] {KEY_ROWID,KEY_NAME,KEY_PRICE};
Log.w("my app", "deleteOrderEntry Top");
Cursor c = ourDatabase.query(DATABASE_TABLE, columns, KEY_ROWID + "= " + Integer.toString(lRow) , null, null, null, null);
Log.w("my app", "deleteOrderEntry 2");
if(c!= null)
{
c.moveToFirst();
String nameItem = c.getString(1);
ourDatabase.delete("Bill", "name = '"+ nameItem+ "'", null);
Log.w("my app", "deleteOrderEntry MIDDLE");
return true;
}
return false;
}
public void truncateBill(){
ourDatabase.execSQL("DELETE FROM Bill");
ourDatabase.execSQL("VACUUM");
}
}
推荐答案
您不能写入到存储在您的资产文件夹，因为这是你的apk的一部分，不能改变一个数据库。
You cannot write to a database that is stored in your assets folder as that is part of your apk and cannot be changed.
当你的应用程序运行，你应该检查数据库的存在（在正常数据库文件夹），如果它不存在，从你的资产文件夹，使用复制的数据库来代替。
When your app runs you should check for the existence of a database (in the normal databases folder) and if it does not exist, copy the database from your assets folder and use that instead.
有关详细信息，请参阅以下链接。
See these links for more info.
http://www.devx.com/wireless/Article/40842
<一个href="http://stackoverflow.com/questions/513084/how-to-ship-an-android-application-with-a-database">How出货Android应用程序与数据库？
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