我是Android开发的新手。我正在尝试使用预先填充的数据库，该数据库存储在我的资源文件夹中。日志显示数据库已打开，但显示“NO SUCH TABLE ERROR”。我找不到任何解决此错误的方法。请帮忙。
MyDatabase.java：
package com.example.android.atlas;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteQueryBuilder;
import com.readystatesoftware.sqliteasset.SQLiteAssetHelper;
/**
* Created by Deep on 22-06-2015.
*/
public class MyDatabase extends SQLiteAssetHelper {
private static final String DATABASE_NAME = "appver-1.db";
private static final int DATABASE_VERSION = 1;
public MyDatabase(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
// you can use an alternate constructor to specify a database location
// (such as a folder on the sd card)
// you must ensure that this folder is available and you have permission
// to write to it
//super(context, DATABASE_NAME, context.getExternalFilesDir(null).getAbsolutePath(), null, DATABASE_VERSION);
}
public SQLiteDatabase getData() {
SQLiteDatabase db = getReadableDatabase();
return db;
}
}
PlayActivity.java
public class PlayActivity extends Activity {
private MyDatabase db;
private SQLiteDatabase dbh;
private Cursor togo;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
db = new MyDatabase(this);
dbh = db.getData();
setContentView(R.layout.activity_play);
}
public void onClickGo(View view){
String nm1;
String nm2;
String nm3;
String sendsql,send;
char last;
int l;
TextView tv2_text, tv4_text;
EditText et1_input;
tv2_text = (TextView)findViewById(R.id.tv2_text);
tv4_text = (TextView)findViewById(R.id.tv4_text);
et1_input = (EditText)findViewById(R.id.et1_input);
nm1 = et1_input.getText().toString();
l = nm1.length();
last = nm1.charAt(l - 1);
nm2 = "Africa";
nm3 = "A";
sendsql = "Select PLACES from countries where PLACES like " + "'" + nm3 + "%'" + " LIMIT 1" ;
togo = dbh.rawQuery(sendsql,null);
togo.moveToFirst();
send = togo.getString(0);
tv2_text.setText(send);
tv4_text.setText("A");
}
LOGCAT结果：
06-23 11:57:57.193 2330-2330/? I/SQLiteAssetHelper﹕ successfully opened database appver-1.db
06-23 11:57:57.294 2330-2345/? W/EGL_emulation﹕ eglSurfaceAttrib not implemented
06-23 11:57:57.294 2330-2345/? W/OpenGLRenderer﹕ Failed to set EGL_SWAP_BEHAVIOR on surface 0xa5d8a300, error=EGL_SUCCESS
06-23 11:57:57.497 1234-1257/? I/ActivityManager﹕ Displayed com.example.android.atlas/.PlayActivity: +346ms
06-23 11:57:57.623 2330-2345/? D/OpenGLRenderer﹕ endAllStagingAnimators on 0xa6d6e400 (RippleDrawable) with handle 0xae1bb990
06-23 11:57:58.842 2330-2330/? E/SQLiteLog﹕ (1) no such table: COUNTRIES
06-23 11:57:58.843 2330-2330/? D/AndroidRuntime﹕ Shutting down VM
06-23 11:57:58.843 2330-2330/? E/AndroidRuntime﹕ FATAL EXCEPTION: main
Process: com.example.android.atlas, PID: 2330
java.lang.IllegalStateException: Could not execute method of the activity
at android.view.View$1.onClick(View.java:4007)
at android.view.View.performClick(View.java:4756)
at android.view.View$PerformClick.run(View.java:19749)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5221)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)
Caused by: java.lang.reflect.InvocationTargetException
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at android.view.View$1.onClick(View.java:4002)
at android.view.View.performClick(View.java:4756)
at android.view.View$PerformClick.run(View.java:19749)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5221)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)
Caused by: android.database.sqlite.SQLiteException: no such table: COUNTRIES (code 1): , while compiling: SELECT * FROM COUNTRIES
at android.database.sqlite.SQLiteConnection.nativePrepareStatement(Native Method)
at android.database.sqlite.SQLiteConnection.acquirePreparedStatement(SQLiteConnection.java:889)
at android.database.sqlite.SQLiteConnection.prepare(SQLiteConnection.java:500)
at android.database.sqlite.SQLiteSession.prepare(SQLiteSession.java:588)
at android.database.sqlite.SQLiteProgram.<init>(SQLiteProgram.java:58)
at android.database.sqlite.SQLiteQuery.<init>(SQLiteQuery.java:37)
at android.database.sqlite.SQLiteDirectCursorDriver.query(SQLiteDirectCursorDriver.java:44)
at android.database.sqlite.SQLiteDatabase.rawQueryWithFactory(SQLiteDatabase.java:1316)
at android.database.sqlite.SQLiteDatabase.rawQuery(SQLiteDatabase.java:1255)
at com.example.android.atlas.PlayActivity.onClickGo(PlayActivity.java:53)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at android.view.View$1.onClick(View.java:4002)
at android.view.View.performClick(View.java:4756)
at android.view.View$PerformClick.run(View.java:19749)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5221)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)
06-23 11:57:58.851 1234-1508/? W/ActivityManager﹕ Force finishing activity com.example.android.atlas/.PlayActivity
答案 0 :(得分：1)
如果我没有错，你没有从资产文件夹中复制sqlite数据库。请尝试以下
/**
* 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(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();
}
如果您不是复制数据库，那么您没有这样的表错误。这是一种情况。
答案 1 :(得分：1)
您应该将.db文件从assets文件夹复制到内部/外部存储。您可以使用以下代码
private static String DB_PATH = "/data/data/your package/database/";
private static String DB_NAME ="final.db";// Database name
要创建数据库，
public void createDataBase() throws IOException
{
//If database not exists copy it from the assets
boolean mDataBaseExist = checkDataBase();
if(!mDataBaseExist)
{
try
{
//Copy the database from assests
copyDataBase();
Log.e(TAG, "createDatabase database created");
}
catch (IOException mIOException)
{
throw new Error("ErrorCopyingDataBase");
}
}
}
检查数据库是否存在于：/ data / data / your package / database / DB Name
private boolean checkDataBase()
{
File dbFile = new File(DB_PATH + DB_NAME);
return dbFile.exists();
}
从资产中复制数据库
private void copyDataBase() throws IOException
{
InputStream mInput = getApplicationContext().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();
}
我希望它可以帮助你。
这link也可以帮助你...
答案 2 :(得分：0)
我认为表名有问题。
目前，您使用“国家/地区”作为表名。