Java 未创建数据库表

我试图从数据库中选择数据，但它从未被创建。。。我的代码：

private static final String DATABASE_NAME = "ckredisDB.db";
private static final int DATABASE_VERSION = 1;
/* ALL COLUMNS */
public static final String TABLE_ORDERS = "orders";
public static final String COLUMN_ID = "_id";
public static final String COLUMN_CUSTOMER_ID = "customerId";
public static final String COLUMN_RECEIVER_ID = "receiverId";
public static final String COLUMN_IMPORTANCE = "importance";
public static final String COLUMN_COMMENT = "comment";
public static final String COLUMN_DATE = "date";
/* ALL COLUMNS ARRAY */
private String[] allColumns = {
        COLUMN_ID,
        COLUMN_CUSTOMER_ID,
        COLUMN_RECEIVER_ID,
        COLUMN_IMPORTANCE,
        COLUMN_COMMENT,
        COLUMN_DATE
};

// Database creation sql statement
private static final String DATABASE_CREATE = "create table "
        + TABLE_ORDERS + "(" + COLUMN_ID + " integer primary key autoincrement, "
        + COLUMN_CUSTOMER_ID + " integer not null, "
        + COLUMN_RECEIVER_ID + " integer not null, "
        + COLUMN_IMPORTANCE + " integer not null, "
        + COLUMN_COMMENT + " varchar(255), "
        + COLUMN_DATE + " varchar(10) not null);";

private SQLiteDatabase database;

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

@Override
public void onCreate(SQLiteDatabase database) {
    database.execSQL(DATABASE_CREATE);
    database.execSQL("CREATE INDEX " + TABLE_ORDERS +"_receiverId_index ON " + TABLE_ORDERS + "(" + COLUMN_RECEIVER_ID + ")");
    database.execSQL("CREATE INDEX " + TABLE_ORDERS +"_customerId_index ON " + TABLE_ORDERS + "(" + COLUMN_CUSTOMER_ID + ")");
}

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

    db.execSQL("DROP TABLE IF EXISTS " + TABLE_ORDERS);
    onCreate(db);
}

public Cursor getAllEntries() {
    SQLiteDatabase db = this.getWritableDatabase();
    //this.open();
    Cursor cursor = db.query(TABLE_ORDERS, allColumns, null, null, null, null, null);
    if(cursor != null) cursor.moveToFirst();
    //this.close();
    db.close();
    return cursor;
}

然后，当我试图在主活动游标c=ordHelp.getAllEntries中检索数据库中的所有条目时；我得到一个例外：

02-19 12:17:47.265  20485-20485/com.TrueCKredis E/SQLiteLog﹕ (1) no such table: orders 02-19 12:17:47.273  20485-20485/com.TrueCKredis E/AndroidRuntime﹕ FATAL EXCEPTION: main    java.lang.RuntimeException: Unable to start activity ComponentInfo{com.TrueCKredis/com.TrueCKredis.MainActivity}: android.database.sqlite.SQLiteException: no such table: orders (code 1): , while compiling: SELECT _id, customerId, receiverId, importance, comment, date FROM orders
           at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2129)
           at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2154)
           at android.app.ActivityThread.access$700(ActivityThread.java:146)
           at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1260)
           at android.os.Handler.dispatchMessage(Handler.java:99)
           at android.os.Looper.loop(Looper.java:137)
           at android.app.ActivityThread.main(ActivityThread.java:4949)
           at java.lang.reflect.Method.invokeNative(Native Method)
           at java.lang.reflect.Method.invoke(Method.java:511)
           at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1043)
           at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:810)
           at dalvik.system.NativeStart.main(Native Method)
    Caused by: android.database.sqlite.SQLiteException: no such table: orders (code 1): , while compiling: SELECT _id, customerId, receiverId, importance, comment, date FROM orders
           at android.database.sqlite.SQLiteConnection.nativePrepareStatement(Native Method)
           at android.database.sqlite.SQLiteConnection.acquirePreparedStatement(SQLiteConnection.java:1013)
           at android.database.sqlite.SQLiteConnection.prepare(SQLiteConnection.java:624)
           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:1314)
           at android.database.sqlite.SQLiteDatabase.queryWithFactory(SQLiteDatabase.java:1161)
           at android.database.sqlite.SQLiteDatabase.query(SQLiteDatabase.java:1032)
           at android.database.sqlite.SQLiteDatabase.query(SQLiteDatabase.java:1200)
           at com.TrueCKredis.SQLiteHelper.OrderHelper.getAllEntries(OrderHelper.java:117)
           at com.TrueCKredis.MainActivity.onCreate(MainActivity.java:50)
           at android.app.Activity.performCreate(Activity.java:5185)
           at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1094)
           at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2093)
            at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2154)
            at android.app.ActivityThread.access$700(ActivityThread.java:146)
            at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1260)
            at android.os.Handler.dispatchMessage(Handler.java:99)
            at android.os.Looper.loop(Looper.java:137)
            at android.app.ActivityThread.main(ActivityThread.java:4949)
            at java.lang.reflect.Method.invokeNative(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:511)
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1043)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:810)
            at dalvik.system.NativeStart.main(Native Method)

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您的代码似乎没有问题

您必须在数据库中做了一些更改，并且正在运行的数据库版本较旧

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我建议您卸载该应用程序一次，然后尝试使用新的升级版本安装它。以便反映出来。

卸载并重新安装应用程序。可能您有一个版本号相同的旧数据库文件，因此未调用onCreate/onUpgrade。没有证据表明曾经调用过com.TrueCKredis.SQLiteHelper.OrderHelper.onCreate。你能验证一下吗？卸载应用程序很有帮助，谢谢。TABLE_ORDERS+_receiverId_index，TABLE_ORDERS+u是索引的前缀，添加空间会引发语法错误这是一个常见问题，因此我决定用它创建一个社区wiki：