没有从数据库中获取新创建的表答案

【问题标题】：Not getting new created table from the database没有从数据库中获取新创建的表
【发布时间】：2011-11-08 03:37:41
【问题描述】：

我的数据库适配器代码如下：

package com.quiz.spellingquiz;
import java.io.IOException;

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.SQLiteOpenHelper;
import android.media.MediaPlayer;
import android.media.MediaRecorder;
import android.os.Environment;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;

public class DBAdapter 
{
    //  Database Operation
    public static final String KEY_ROWID = "_id";
    public static final String KEY_ISBN = "isbn";
    public static final String KEY_TITLE = "title";
    public static final String KEY_WORD = "word";
    public static final String KEY_SOUND = "sound";
    public static final String KEY_PUBLISHER = "publisher";    
    private static final String TAG = "DBAdapter";
    private static final String DATABASE_NAME = "testing";
    public static String DATABASE_TABLE = null;
    private static final int DATABASE_VERSION = 1;

    public static final String DATABASE_CREATE =
        "create table "+DATABASE_TABLE+" (_id integer primary key, "
        + "isbn text not null," 
        + "title text not null,"
        + "word text not null,"
        + "sound text not null,"
        + "publisher text not null);";


    private final Context context; 

    private DatabaseHelper DBHelper;
    private SQLiteDatabase db;


    public DBAdapter(Context ctx, String table_name) 
    {
        this.context = ctx;
        DATABASE_TABLE=table_name;
        DBHelper = new DatabaseHelper(context);
    }

    private static class DatabaseHelper extends SQLiteOpenHelper 
    {
        DatabaseHelper(Context context) 
        {
            super(context, DATABASE_NAME, null, DATABASE_VERSION);
        }

        @Override
        public void onCreate(SQLiteDatabase db) 
        {
            db.execSQL(DATABASE_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 "+DATABASE_TABLE);
            onCreate(db);
        }
    }    

    //---opens the database---
    public DBAdapter open() throws SQLException 
    {
        db = DBHelper.getWritableDatabase();
        return this;
    }

    //---closes the database---    
    public void close() 
    {
        DBHelper.close();
    }

    //---insert a title into the database---
    public long insertTitle(String isbn, String title, String word, String sound, String publisher) 
    {
        ContentValues initialValues = new ContentValues();
        initialValues.put(KEY_ISBN, isbn);
        initialValues.put(KEY_TITLE, title);
        initialValues.put(KEY_WORD, word);
        initialValues.put(KEY_SOUND, sound);
        initialValues.put(KEY_PUBLISHER, publisher);
        return db.insert(DATABASE_TABLE, null, initialValues);
    }

    //---deletes a particular title---
    public boolean deleteTitle(long rowId) 
    {
        return db.delete(DATABASE_TABLE, KEY_ROWID + "=" + rowId, null) > 0;
    }

    public boolean deleteAllTitle()
    {
        return db.delete(DATABASE_TABLE,null, null)>0;
    }
    public Cursor getAllTitles() 
    {
        Cursor mCursor = db.query(DATABASE_TABLE, new String[] {
                KEY_ROWID, 
                KEY_ISBN,
                KEY_TITLE,
                KEY_WORD,
                KEY_SOUND,
                KEY_PUBLISHER}, 
                null, 
                null, 
                null,
                null, 
                null,
                null);

        return mCursor;
    }


    //---retrieves a particular title---
    public Cursor getTitle(long rowId) throws SQLException 
    {
        Cursor mCursor = db.query(true, DATABASE_TABLE, new String[] {
                        KEY_ROWID,
                        KEY_ISBN, 
                        KEY_TITLE,
                        KEY_WORD,
                        KEY_SOUND,
                        KEY_PUBLISHER
                        }, 
                        KEY_ROWID + "=" + rowId, 
                        null,
                        null, 
                        null, 
                        null, ////////////////////////////
                        null);
        if (mCursor != null) 
        {
            mCursor.moveToFirst();
        }
        return mCursor;
    }
    // to fetch TextFile with Sound file
    public Cursor getSound(String str) throws SQLException
    {
        String file = Environment.getExternalStorageDirectory().getAbsolutePath();
        file = file+"/"+str+".3gp";

        Cursor mCursor = db.query(true, DATABASE_TABLE, new String[] {
                    KEY_ROWID,
                    KEY_ISBN, 
                    KEY_TITLE,
                    KEY_WORD,
                    KEY_SOUND,
                    KEY_PUBLISHER
                }, 
                KEY_SOUND + "=" +file, 
                null,
                null, 
                null, 
                null,
                null);
if (mCursor != null) 
{
    mCursor.moveToFirst();
}
return mCursor;

    }

    public void deleteAll()
    {
        this.db.delete(DATABASE_TABLE, null, null);
    }

    //---updates a title---
    public boolean updateTitle(long rowId, String isbn, String title,String word,String sound, String publisher) 
    {
        ContentValues args = new ContentValues();
        args.put(KEY_ISBN, isbn);
        args.put(KEY_TITLE, title);
        args.put(KEY_WORD, word);
        args.put(KEY_SOUND, sound);
        args.put(KEY_PUBLISHER, publisher);
        return db.update(DATABASE_TABLE, args, KEY_ROWID + "=" + rowId, null) > 0;
    }
}

现在在另一个活动中，我使用如下表名创建 DatabaseAdapter 对象：

final DBAdapter db = new DBAdapter(this,table_name); // create new database with givan table name

现在，当我从该对象获取数据时，它给了我这样的错误：

android.database.sqlite.SQLiteException: no such table: hello: , while compiling: INSERT INTO hello(word, title, sound, publisher, isbn) VALUES(?, ?, ?, ?, ?);

那么我哪里错了？为什么我无法创建表？我该怎么办？

查看这是我调用 DBAdapter 的另一个活动的代码

  // database object        
    final DBAdapter db = new DBAdapter(this); // create new database with givan table name


    showall.setOnClickListener(new View.OnClickListener() 
    {

        public void onClick(View v) 
        {
            db.open();
            Cursor c = db.getAllTitles();
            while(c.moveToNext())        
            {
                Toast.makeText(EnterWordsActivity.this,
                        "id: " + c.getString(0) + "\n" + 
                        "ISBN: " + c.getString(1) + "\n" +  
                        "TITLE: " + c.getString(2) + "\n" + 
                        "WORD: " + c.getString(3) + "\n" +
                        "SOUND:" + c.getString(4) +"\n"+
                        "PUBLISHER:  " + c.getString(5),Toast.LENGTH_LONG).show();
            }
            db.close();
        }
    });

在同一数据库中创建新表后的错误日志。

09-01 15:05:52.608: ERROR/AndroidRuntime(596): FATAL EXCEPTION: main

09-01 15:05:52.608: ERROR/AndroidRuntime(596): android.database.sqlite.SQLiteException: no such table: world: , while compile: SELECT _id, isbn, title, word, sound, publisher FROM世界 09-01 15:05:52.608：错误/AndroidRuntime（596）：在 android.database.sqlite.SQLiteCompiledSql.native_compile（本机方法） 09-01 15:05:52.608: 错误/AndroidRuntime(596): 在 android.database.sqlite.SQLiteCompiledSql.compile(SQLiteCompiledSql.java:91) 09-01 15:05:52.608: 错误/AndroidRuntime(596): 在 android.database.sqlite.SQLiteCompiledSql.(SQLiteCompiledSql.java:64) 09-01 15:05:52.608: 错误/AndroidRuntime(596): 在 android.database.sqlite.SQLiteProgram.(SQLiteProgram.java:80) 09-01 15:05:52.608: 错误/AndroidRuntime(596): 在 android.database.sqlite.SQLiteQuery.(SQLiteQuery.java:46) 09-01 15:05:52.608: 错误/AndroidRuntime(596): 在 android.database.sqlite.SQLiteDirectCursorDriver.query(SQLiteDirectCursorDriver.java:42) 09-01 15:05:52.608: 错误/AndroidRuntime(596): 在 android.database.sqlite.SQLiteDatabase.rawQueryWithFactory(SQLiteDatabase.java:1345) 09-01 15:05:52.608: 错误/AndroidRuntime(596): 在 android.database.sqlite.SQLiteDatabase.queryWithFactory(SQLiteDatabase.java:1229) 09-01 15:05:52.608: 错误/AndroidRuntime(596): 在 android.database.sqlite.SQLiteDatabase.query(SQLiteDatabase.java:1184) 09-01 15:05:52.608: 错误/AndroidRuntime(596): 在 android.database.sqlite.SQLiteDatabase.query(SQLiteDatabase.java:1301) 09-01 15:05:52.608: 错误/AndroidRuntime(596): 在 com.quiz.spellingquiz.DBAdapter.getAllTitles(DBAdapter.java:119) 09-01 15:05:52.608: 错误/AndroidRuntime(596): 在 com.quiz.spellingquiz.EnterWordsActivity$1.onClick(EnterWordsActivity.java:86) 09-01 15:05:52.608: 错误/AndroidRuntime(596): 在 android.view.View.performClick(View.java:2408) 09-01 15:05:52.608: 错误/AndroidRuntime(596): 在 android.view.View$PerformClick.run(View.java:8816) 09-01 15:05:52.608: 错误/AndroidRuntime(596): 在 android.os.Handler.handleCallback(Handler.java:587) 09-01 15:05:52.608: 错误/AndroidRuntime(596): 在 android.os.Handler.dispatchMessage(Handler.java:92) 09-01 15:05:52.608: 错误/AndroidRuntime(596): 在 android.os.Looper.loop(Looper.java:123) 09-01 15:05:52.608: 错误/AndroidRuntime(596): 在 android.app.ActivityThread.main(ActivityThread.java:4627) 09-01 15:05:52.608: 错误/AndroidRuntime(596): 在 java.lang.reflect.Method.invokeNative(Native Method) 09-01 15:05:52.608: 错误/AndroidRuntime(596): 在 java.lang.reflect.Method.invoke(Method.java:521) 09-01 15:05:52.608: 错误/AndroidRuntime(596): 在 com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868) 09-01 15:05:52.608: 错误/AndroidRuntime(596): 在 com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626) 09-01 15:05:52.608: 错误/AndroidRuntime(596): at dalvik.system.NativeStart.main(Native Method)

【问题讨论】：

标签： android android-layout android-emulator android-widget android-ndk

【解决方案1】：

我认为这里的问题是您没有为您的数据库名称声明 .db 扩展名

 private static final String DATABASE_NAME = "testing";

应该是

 private static final String DATABASE_NAME = "testing.db";

这肯定行得通，因为我试过你的代码。

还有一个变化是这样的

@Override
        public void onCreate(SQLiteDatabase db) 
        {
            db.execSQL("create table "+DATABASE_TABLE+" (_id integer primary key, "
                    + "isbn text not null," 
                    + "title text not null,"
                    + "word text not null,"
                    + "sound text not null,"
                    + "publisher text not null);");
        }

添加上面的代码而不是

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

那么就这样调用这个类，

DBAdapter adapter = new DBAdapter(this,"mytable");

【讨论】：

好的。谢谢回复。但是请参阅我更新的问题，我将一些代码放在我要创建和调用 DBAdapter 对象的位置。那么，如果我还想将表名提供给 DBAdapter 类，我应该怎么做？？？然后应该只使用该名称创建表。
我已经解决了你的问题。就按照我的回答去做，你就完成了，然后打电话给你的班级。
是的，苏瑞。 . . .非常感谢。所以在这种情况下每次表都会是新的吧？？？
好吧，我还没有在数据库上做那么多工作。也谢谢你。
这里有一个问题。 ..如果我创建新数据库和新表，那么它工作得很好，但是如果我在该数据库中创建新表，那么它就会崩溃并告诉我没有带有新添加名称的这样的表？现在我哪里错了？

【解决方案2】：

使用此代码

 import java.io.IOException;

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.SQLiteOpenHelper;
import android.media.MediaPlayer;
import android.media.MediaRecorder;
import android.os.Environment;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;

public class DBAdapter 
{
//  Database Operation
public static final String KEY_ROWID = "_id";
public static final String KEY_ISBN = "isbn";
public static final String KEY_TITLE = "title";
public static final String KEY_WORD = "word";
public static final String KEY_SOUND = "sound";
public static final String KEY_PUBLISHER = "publisher";    
private static final String TAG = "DBAdapter";
private static final String DATABASE_NAME = "testing";
public static String DATABASE_TABLE = null;
private static final int DATABASE_VERSION = 1;

public static final String DATABASE_CREATE =
    "create table "+DATABASE_TABLE+" (_id integer primary key, "
    + "isbn text not null," 
    + "title text not null,"
    + "word text not null,"
    + "sound text not null,"
    + "publisher text not null);";


private final Context context; 

private DatabaseHelper DBHelper;
private SQLiteDatabase db;


public DBAdapter(Context ctx, String table_name) 
{
    this.context = ctx;
    DATABASE_TABLE=table_name;
    DBHelper = new DatabaseHelper(context);
}

private static class DatabaseHelper extends SQLiteOpenHelper 
{
    DatabaseHelper(Context context) 
    {
        super(context, DATABASE_NAME, null, DATABASE_VERSION);
    }

    @Override
    public void onCreate(SQLiteDatabase db) 
    {
        db.execSQL(DATABASE_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 "+DATABASE_TABLE);
        onCreate(db);
    }
}    

//---opens the database---
public DBAdapter open() throws SQLException 
{
    db = DBHelper.getWritableDatabase();
    return this;
}

//---closes the database---    
public void close() 
{
    DBHelper.close();
}

//used to create the the new table
public void createNewTable(String t_name){
    this.DATABASE_TABLE=t_name;
    db.execSQL(this.DATABASE_CREATE);
}


//---insert a title into the database---
public long insertTitle(String isbn, String title, String word, String sound, String publisher) 
{
    ContentValues initialValues = new ContentValues();
    initialValues.put(KEY_ISBN, isbn);
    initialValues.put(KEY_TITLE, title);
    initialValues.put(KEY_WORD, word);
    initialValues.put(KEY_SOUND, sound);
    initialValues.put(KEY_PUBLISHER, publisher);
    return db.insert(DATABASE_TABLE, null, initialValues);
}

//---deletes a particular title---
public boolean deleteTitle(long rowId) 
{
    return db.delete(DATABASE_TABLE, KEY_ROWID + "=" + rowId, null) > 0;
}

public boolean deleteAllTitle()
{
    return db.delete(DATABASE_TABLE,null, null)>0;
}
public Cursor getAllTitles() 
{
    Cursor mCursor = db.query(DATABASE_TABLE, new String[] {
            KEY_ROWID, 
            KEY_ISBN,
            KEY_TITLE,
            KEY_WORD,
            KEY_SOUND,
            KEY_PUBLISHER}, 
            null, 
            null, 
            null,
            null, 
            null,
            null);

    return mCursor;
}


//---retrieves a particular title---
public Cursor getTitle(long rowId) throws SQLException 
{
    Cursor mCursor = db.query(true, DATABASE_TABLE, new String[] {
                    KEY_ROWID,
                    KEY_ISBN, 
                    KEY_TITLE,
                    KEY_WORD,
                    KEY_SOUND,
                    KEY_PUBLISHER
                    }, 
                    KEY_ROWID + "=" + rowId, 
                    null,
                    null, 
                    null, 
                    null, ////////////////////////////
                    null);
    if (mCursor != null) 
    {
        mCursor.moveToFirst();
    }
    return mCursor;
}
// to fetch TextFile with Sound file
public Cursor getSound(String str) throws SQLException
{
    String file = Environment.getExternalStorageDirectory().getAbsolutePath();
    file = file+"/"+str+".3gp";

    Cursor mCursor = db.query(true, DATABASE_TABLE, new String[] {
                KEY_ROWID,
                KEY_ISBN, 
                KEY_TITLE,
                KEY_WORD,
                KEY_SOUND,
                KEY_PUBLISHER
            }, 
            KEY_SOUND + "=" +file, 
            null,
            null, 
            null, 
            null,
            null);
    if (mCursor != null) 
  { 
   mCursor.moveToFirst();
  }
 return mCursor;

}

public void deleteAll()
{
    this.db.delete(DATABASE_TABLE, null, null);
}

//---updates a title---
public boolean updateTitle(long rowId, String isbn, String title,String word,String sound, String publisher) 
{
    ContentValues args = new ContentValues();
    args.put(KEY_ISBN, isbn);
    args.put(KEY_TITLE, title);
    args.put(KEY_WORD, word);
    args.put(KEY_SOUND, sound);
    args.put(KEY_PUBLISHER, publisher);
    return db.update(DATABASE_TABLE, args, KEY_ROWID + "=" + rowId, null) > 0;
}

}

在你的活动中

db.open();
      db.createNewTable("ur table name");

这解决了你的问题

【讨论】：

是的，它工作正常，现在我可以在现有数据库中创建新表。但是第一个创建的表呢？
旧表丢失还是保存在数据库中？我怎么知道呢？
我仍然没有得到你的答案，我之前创建的旧表是什么？因为我看不到它。 . .
旧表还在数据库中
是的，我已经检查过了。伟大的。谢谢。你能帮我多一点吗？？我想在数据库中显示所有可用的表？怎么可能？或者有没有可能？

【解决方案3】：

一开始，当final string DATABASE_CREATE 被创建时，string DATABASE_TABLE 将是null。所以每次使用DATABASE_CREATE，查询是：

DATABASE_CREATE = "create table (_id integer primary key, "
    + "isbn text not null," 
    + "title text not null,"
    + "word text not null,"
    + "sound text not null,"
    + "publisher text not null);"

这个查询（没有表名）无效。

=== 更新 ===

在string DATABASE_CREATE 中将变量DATABASE_TABLE 替换为模板名称：

public static final String DATABASE_CREATE =
    "create table #table_name# (_id integer primary key, "
    + "isbn text not null," 
    + "title text not null,"
    + "word text not null,"
    + "sound text not null,"
    + "publisher text not null);";

并替换onCreate中的模板名称：

@Override
public void onCreate(SQLiteDatabase db) 
{
    String query = DATABASE_CREATE.replace("#table_name#", DATABASE_TABLE);
    db.execSQL(query);
}

【讨论】：

好的。那我该怎么办？请参考我的整个程序。我在从其他活动创建 DatabaseAdapter 时给出了表名。
@iDroid Explorer 首先删除 DATABASE_TABLE = null;并尝试使用 DATABASE_TABLE = "";
@scessor ：它不工作。 :-( 它给了我像无效令牌这样的错误。
如果您使用'#table_name#'请在onCreate()中替换为"#table_name#"。
我仍然无法创建该表。 Lkistern table_name 是我在调用 Databaseadapter 时传递的值。请参阅 DatabaseAdatpeter 的构造函数。

【解决方案4】：

如果您的新更改设置未显示，那么我认为您应该更新数据库版本。这将执行新的更改并保存它们

【讨论】：