android中的sqlite数据库错误

我正在尝试创建一个包含3个表的数据库并将数据插入其中一个表中。

数据库和表的创建都非常完美，但是我无法将数据插入到一个表中。

DbOperations.java

package com.example.word_a_diction;
import com.example.word_a_diction.TableData.TableInfo;
import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteDatabase.CursorFactory;
import android.database.sqlite.SQLiteOpenHelper;
import android.util.Log;

public class DbOperations extends SQLiteOpenHelper {

    public static final int Db_Version = 1;
    SQLiteDatabase sqldb;

    public DbOperations(Context context) {

        super(context, TableInfo.Db_Name, null, Db_Version);
        System.out.println("Db Operations----Db Created");
    }
    @Override
    public void onCreate(SQLiteDatabase sdb) {
            sdb.execSQL("CREATE TABLE "+TableInfo.Table1+
            " ( "+TableInfo.S_no+" INTEGER PRIMARY KEY
             AUTOINCREMENT ,"+TableInfo.Word+" TEXT UNIQUE ,"
            +TableInfo.Ans+" TEXT , "+TableInfo.Opt1+" TEXT ,"
            +TableInfo.Opt2+" TEXT ,"+TableInfo.Opt3+" TEXT ,"
            +TableInfo.Opt4+" TEXT ,"+TableInfo.M1+" TEXT ,"
            +TableInfo.M2+" TEXT ,"+TableInfo.M3+" TEXT ,"
            +TableInfo.M4+" TEXT );");
       System.out.println("db operations-----table1 created");
       sdb.execSQL("CREATE TABLE "+TableInfo.Table2+
        " ( "+TableInfo.S_no+" INTEGER PRIMARY KEY AUTOINCREMENT,        "+TableInfo.Word+" TEXT ,"
            +TableInfo.Ans+" TEXT ,"+TableInfo.Opt1+" TEXT ,"
            +TableInfo.Opt2+" TEXT ,"+TableInfo.Opt3+" TEXT ,"
            +TableInfo.Opt4+" TEXT ,"+TableInfo.M1+" TEXT ,"
            +TableInfo.M2+" TEXT ,"+TableInfo.M3+" TEXT ,"
            +TableInfo.M4+" TEXT);");
    System.out.println("db operations-----table2 created");
    sdb.execSQL("CREATE TABLE "+TableInfo.Table3+
            " ( "+TableInfo.S_no+" INTEGER PRIMARY KEY AUTOINCREMENT , "+TableInfo.Word+" TEXT ,"
            +TableInfo.Ans+" TEXT ,"+TableInfo.Opt1+" TEXT ,"
            +TableInfo.Opt2+" TEXT ,"+TableInfo.Opt3+" TEXT ,"
            +TableInfo.Opt4+" TEXT ,"+TableInfo.M1+" TEXT ,"
            +TableInfo.M2+" TEXT ,"+TableInfo.M3+" TEXT ,"
            +TableInfo.M4+" TEXT);");
    System.out.println("db operations---table3 created");

    insertValues();
}

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

    db.execSQL("DROP TABLE IF EXISTS "+TableInfo.Table1+";");
    db.execSQL("DROP TABLE IF EXISTS "+TableInfo.Table2+";");
    db.execSQL("DROP TABLE IF EXISTS "+TableInfo.Table3+";");
    onCreate(db);

}

public void insertValues()
{
    //open();
    //sqldb = this.getWritableDatabase();
    sqldb.execSQL("INSERT INTO BASIC VALUES ('Debonair','Sophisticated,charming','Careful'," +
            "'Well-read','Sly','Sophisticated,charming','Using care','Knowledgeable'," +
            "'Clever in a dishonest way,Cunning'," +
            "'Having a refined knowledge of the ways of the world');");
    System.out.println("data inserted");

}
public DbOperations open() {
    sqldb = this.getWritableDatabase();
    return this;
}
public void close(){
    sqldb.close();
}
}

TableData.java

package com.example.word_a_diction;
import android.provider.BaseColumns;
public class TableData {

public TableData()
{

}

public static abstract class TableInfo implements BaseColumns
{
    public static final String S_no = "SNo";
    public static final String Word = "Word";
    public static final String Ans = "Ans";
    public static final String Opt1 = "Opt1";
    public static final String Opt2 = "Opt2";
    public static final String Opt3 = "Opt3";
    public static final String Opt4 = "Opt4";
    public static final String M1 = "M1";
    public static final String M2 = "M2";
    public static final String M3 = "M3";
    public static final String M4 = "M4";
    public static final String Db_Name = "ListOfWords";
    public static final String Table1 = "BASIC";
    public static final String Table2 = "INTER";
    public static final String Table3 = "SKILLED";
  }
 }

QSkilled.java

  package com.example.word_a_diction;
  import android.app.Activity;
  import android.content.Intent;
  import android.os.Bundle;
  import android.speech.tts.TextToSpeech;
  import android.speech.tts.TextToSpeech.OnInitListener;
  import android.view.View;
  import android.view.View.OnClickListener;
  import android.widget.ImageButton;
  import android.widget.RadioButton;
  import android.widget.TextView;
  import android.widget.Toast;

  public class QSkilled extends Activity
  {
        private DbOperations db1;
        public void onCreate(Bundle b)
        {
           super.onCreate(b);
           setContentView(R.layout.q_skilled);
            db1 = new DbOperations(this);
            db1.open();
        }   
        public void onDestroy(){
            db1.close();
        }
}

我在日志中不断收到以下错误。一旦我尝试打开QSkilled.java，该应用程序将被强制关闭。

01-23 09:41:37.875: I/System.out(330): Db Operations----Db Created

01-23 09:41:37.984: I/System.out(330): db operations-----table1 created

01-23 09:41:37.984: I/System.out(330): db operations-----table2 created

01-23 09:41:37.994: I/System.out(330): db operations---table3 created

01-23 09:41:38.048: D/AndroidRuntime(330): Shutting down VM

01-23 09:41:38.054: W/dalvikvm(330): threadid=1: thread exiting with uncaught exception (group=0x40015560)

01-23 09:41:38.076: E/AndroidRuntime(330): FATAL EXCEPTION: main

01-23 09:41:38.076: E/AndroidRuntime(330): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.word_a_diction/com.example.word_a_diction.QSkilled}: java.lang.NullPointerException

01-23 09:41:38.076: E/AndroidRuntime(330):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1647)

01-23 09:41:38.076: E/AndroidRuntime(330):  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1663)

01-23 09:41:38.076: E/AndroidRuntime(330):  at android.app.ActivityThread.access$1500(ActivityThread.java:117)

01-23 09:41:38.076: E/AndroidRuntime(330):  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:931)

01-23 09:41:38.076: E/AndroidRuntime(330):  at android.os.Handler.dispatchMessage(Handler.java:99)

01-23 09:41:38.076: E/AndroidRuntime(330):  at android.os.Looper.loop(Looper.java:123)

01-23 09:41:38.076: E/AndroidRuntime(330):  at android.app.ActivityThread.main(ActivityThread.java:3683)

01-23 09:41:38.076: E/AndroidRuntime(330):  at java.lang.reflect.Method.invokeNative(Native Method)

01-23 09:41:38.076: E/AndroidRuntime(330):  at java.lang.reflect.Method.invoke(Method.java:507)

01-23 09:41:38.076: E/AndroidRuntime(330):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)

01-23 09:41:38.076: E/AndroidRuntime(330):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)

01-23 09:41:38.076: E/AndroidRuntime(330):  at dalvik.system.NativeStart.main(Native Method)

01-23 09:41:38.076: E/AndroidRuntime(330): Caused by: java.lang.NullPointerException

01-23 09:41:38.076: E/AndroidRuntime(330):  at com.example.word_a_diction.DbOperations.insertValues(DbOperations.java:72)

01-23 09:41:38.076: E/AndroidRuntime(330):  at com.example.word_a_diction.DbOperations.onCreate(DbOperations.java:55)

01-23 09:41:38.076: E/AndroidRuntime(330):  at android.database.sqlite.SQLiteOpenHelper.getWritableDatabase(SQLiteOpenHelper.java:126)

01-23 09:41:38.076: E/AndroidRuntime(330):  at com.example.word_a_diction.DbOperations.open(DbOperations.java:80)

01-23 09:41:38.076: E/AndroidRuntime(330):  at com.example.word_a_diction.QSkilled.onCreate(QSkilled.java:102)

01-23 09:41:38.076: E/AndroidRuntime(330):  at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)

01-23 09:41:38.076: E/AndroidRuntime(330):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1611)

01-23 09:41:38.076: E/AndroidRuntime(330):  ... 11 more

01-23 09:41:42.975: I/Process(330): Sending signal. PID: 330 SIG: 9