sqlite 오류 추적 파일 열기

Question

나는 안드로이드 프로그래밍에 관해서는 멍청한데, 나는 SQLite를 머리에 쓰는 데 특별한 어려움을 겪고있다. 내 응용 프로그램을 실행할 때 잘로드되지만 오류 "추적 파일 열기 오류 : 해당 파일 또는 디렉터리 (2)"와 함께 제공됩니다.

03-15 17:35:01.523: E/Trace(794): error opening trace file: No such file or directory (2) 
03-15 17:35:02.223: D/gralloc_goldfish(794): Emulator without GPU emulation detected. 
03-15 17:37:48.623: E/SQLiteLog(794): (1) no such column: _id 
03-15 17:37:48.623: D/AndroidRuntime(794): Shutting down VM 
03-15 17:37:48.623: W/dalvikvm(794): threadid=1: thread exiting with uncaught exception (group=0x40a13300) 
03-15 17:37:48.673: E/AndroidRuntime(794): FATAL EXCEPTION: main 
03-15 17:37:48.673: E/AndroidRuntime(794): java.lang.IllegalStateException: Could not execute method of the activity 
03-15 17:37:48.673: E/AndroidRuntime(794): at android.view.View$1.onClick(View.java:3591) 
03-15 17:37:48.673: E/AndroidRuntime(794): at android.view.View.performClick(View.java:4084) 
03-15 17:37:48.673: E/AndroidRuntime(794): at android.view.View$PerformClick.run(View.java:16966) 
03-15 17:37:48.673: E/AndroidRuntime(794): at android.os.Handler.handleCallback(Handler.java:615) 
03-15 17:37:48.673: E/AndroidRuntime(794): at android.os.Handler.dispatchMessage(Handler.java:92) 
03-15 17:37:48.673: E/AndroidRuntime(794): at android.os.Looper.loop(Looper.java:137) 
03-15 17:37:48.673: E/AndroidRuntime(794): at android.app.ActivityThread.main(ActivityThread.java:4745) 
03-15 17:37:48.673: E/AndroidRuntime(794): at java.lang.reflect.Method.invokeNative(Native Method) 
03-15 17:37:48.673: E/AndroidRuntime(794): at java.lang.reflect.Method.invoke(Method.java:511) 
03-15 17:37:48.673: E/AndroidRuntime(794): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786) 
03-15 17:37:48.673: E/AndroidRuntime(794): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553) 
03-15 17:37:48.673: E/AndroidRuntime(794): at dalvik.system.NativeStart.main(Native Method) 
03-15 17:37:48.673: E/AndroidRuntime(794): Caused by: java.lang.reflect.InvocationTargetException 
03-15 17:37:48.673: E/AndroidRuntime(794): at java.lang.reflect.Method.invokeNative(Native Method) 
03-15 17:37:48.673: E/AndroidRuntime(794): at java.lang.reflect.Method.invoke(Method.java:511) 
03-15 17:37:48.673: E/AndroidRuntime(794): at android.view.View$1.onClick(View.java:3586) 
03-15 17:37:48.673: E/AndroidRuntime(794): ... 11 more 
03-15 17:37:48.673: E/AndroidRuntime(794): Caused by: android.database.sqlite.SQLiteException: no such column: _id (code 1): , while compiling: SELECT _id, content FROM exampletable WHERE _id = 4 
03-15 17:37:48.673: E/AndroidRuntime(794): at android.database.sqlite.SQLiteConnection.nativePrepareStatement(Native Method) 
03-15 17:37:48.673: E/AndroidRuntime(794): at android.database.sqlite.SQLiteConnection.acquirePreparedStatement(SQLiteConnection.java:882) 
03-15 17:37:48.673: E/AndroidRuntime(794): at android.database.sqlite.SQLiteConnection.prepare(SQLiteConnection.java:493) 
03-15 17:37:48.673: E/AndroidRuntime(794): at android.database.sqlite.SQLiteSession.prepare(SQLiteSession.java:588) 
03-15 17:37:48.673: E/AndroidRuntime(794): at android.database.sqlite.SQLiteProgram.<init>(SQLiteProgram.java:58) 
03-15 17:37:48.673: E/AndroidRuntime(794): at android.database.sqlite.SQLiteQuery.<init>(SQLiteQuery.java:37) 
03-15 17:37:48.673: E/AndroidRuntime(794): at android.database.sqlite.SQLiteDirectCursorDriver.query(SQLiteDirectCursorDriver.java:44) 
03-15 17:37:48.673: E/AndroidRuntime(794): at android.database.sqlite.SQLiteDatabase.rawQueryWithFactory(SQLiteDatabase.java:1314) 
03-15 17:37:48.673: E/AndroidRuntime(794): at android.database.sqlite.SQLiteDatabase.queryWithFactory(SQLiteDatabase.java:1161) 
03-15 17:37:48.673: E/AndroidRuntime(794): at android.database.sqlite.SQLiteDatabase.query(SQLiteDatabase.java:1032) 
03-15 17:37:48.673: E/AndroidRuntime(794): at android.database.sqlite.SQLiteDatabase.query(SQLiteDatabase.java:1238) 
03-15 17:37:48.673: E/AndroidRuntime(794): at com.example.sqlite.MainActivity.insertButton(MainActivity.java:38) 
03-15 17:37:48.673: E/AndroidRuntime(794): ... 14 more 

내 MainActivity.java :

package com.example.sqlite; 

import android.app.Activity; 
import android.content.ContentValues; 
import android.database.Cursor; 
import android.database.sqlite.SQLiteDatabase; 
import android.os.Bundle; 
import android.view.Menu; 
import android.view.View; 
import android.widget.TextView; 

public class MainActivity extends Activity { 

    DBHelper dbhelper = new DBHelper(this); 

    @Override 
    protected void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.activity_main); 
    } 

    @Override 
    public boolean onCreateOptionsMenu(Menu menu) { 
     // Inflate the menu; this adds items to the action bar if it is present. 
     getMenuInflater().inflate(R.menu.main, menu); 
     return true; 
    } 

    public void insertButton(View view){ 
     SQLiteDatabase db = dbhelper.getWritableDatabase(); 
     ContentValues values = new ContentValues(); 
     values.put("content", "Awesome"); 

     long newRowId = db.insert("exampletable", null, values); 

     String[] projection = {"_id", "content"}; 

     Cursor c = db.query("exampletable", projection, "_id = " + newRowId, null, null, null, null, null); 

     c.moveToFirst(); 

     String content = c.getString(c.getColumnIndex("content")); 

     TextView textView = (TextView) findViewById(R.id.textView1); 
     textView.setText(content); 

    } 

} 

그럼 난 내 데이터베이스에 멋진 문자열을 삽입하고 이러한 오류가 오는 텍스트 뷰 앱 충돌에 반환해야하는 내 버튼을 클릭하면 내 DBHelper.java :

package com.example.sqlite; 

import android.content.Context; 
import android.database.sqlite.SQLiteDatabase; 
import android.database.sqlite.SQLiteOpenHelper; 

public class DBHelper extends SQLiteOpenHelper { 

    public static final int DATABASE_VERSION = 1; 
    public static final String DATABASE_NAME = "ExampleDB"; 

    private String ONCREATE_SQL = "CREATE TABLE exampletable(_id INTEGER PRIMARY KEY AUTOINCREMENT, content TEXT);"; 

    public DBHelper(Context context) { 
     super(context, DATABASE_NAME, null, DATABASE_VERSION); 
    } 

    @Override 
    public void onCreate(SQLiteDatabase db) { 
     db.execSQL(ONCREATE_SQL); 


    } 

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

    } 

} 

무엇이 잘못 되었나요? 초기 오류로 인해 버튼을 클릭 할 때의 오류입니까 아니면 별개입니까? 많은 감사합니다.

Answer 1

데이터베이스에 "_id"열이 없기 때문에 SQL 문을 실행할 수 없습니다. 테이블을 다시 만들려고 했습니까?

확실히 표가 제대로 작성되는 확인 :

은 그냥 DATABASE_VERSION을 증가시키고 onUpgrade 메소드를 구현하십시오 databasse 테이블을 작성하는 동안 오류가 있는지

@Override 
public void onUpgrade(SQLiteDatabase database) { 
    database.execSQL("DROP TABLE IF EXISTS " + TABLE_NAME); 
    onCreate(database); 
} 

가 그런 다음 로그를 확인하십시오. 그렇지 않은 경우 /data/data/packename을보고 SQLite DB를 찾으십시오. pull DDMS 퍼스펙티브이고 테이블이 성공적으로 생성 된 경우 check입니다.