Question

我一直收到关于我的sql数据库的错误

新错误

07-03 01：52：08.037：ERROR / AndroidRuntime（627）：java.lang.RuntimeException：无法启动活动ComponentInfo {com.fttech.books / com.fttech.books.viewBooks}：android.database。 sqlite.SQLiteException：没有这样的列：作者：，同时编译：SELECT book，author，isbn，rating FROM collection

07-03 00：15：04.807：INFO / Database（927）：sqlite返回：错误代码= 1，msg =没有这样的列：book

现在我在新模拟器上收到此错误

07-03 00：33：27.887：INFO / Database（384）：sqlite返回：错误代码= 1，msg =没有这样的表：集合

这是我用过的数据库代码......

public class booksDbAdapter {

    private static final String DATABASE_NAME = "collection";
    private static final String DATABASE_TABLE = "collection";
    private static final int DATABASE_VERSION = 1;

    public static final String KEY_BOOK = "book";
    public static final String KEY_AUTHOR = "author";
    public static final String KEY_ISBN = "isbn";
    public static final String KEY_RATING = "rating";
    public static final String KEY_ROWID = "_id";

    private DatabaseHelper mDbHelper;
    private SQLiteDatabase mDb;

    private static final String DATABASE_CREATE =
                    " create table " + " DATABASE_TABLE " + " ("
                    + KEY_ROWID + " integer primary key autoincrement,      "
                    + KEY_BOOK + " text not null, "
                    + KEY_ISBN + " text not null, "
                    + KEY_RATING + " text not null);";

    private final Context mCtx;

    public booksDbAdapter (Context ctx){
        this.mCtx = ctx;
    }

    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) {
            // TODO Auto-generated method stub
        }
    }
    public booksDbAdapter open() throws SQLException{
        mDbHelper =  new DatabaseHelper(mCtx);
        mDb = mDbHelper.getWritableDatabase();
        return this;
    }
    public void close(){
        mDbHelper.close();
    }

    public long createBook(String book, String author, String isbn, String rating){
        ContentValues initialValues = new ContentValues();
        initialValues.put(KEY_BOOK, book);
        initialValues.put(KEY_AUTHOR, author);
        initialValues.put(KEY_ISBN, isbn);
        initialValues.put(KEY_RATING, rating);

        return mDb.insert(DATABASE_TABLE, null, initialValues);
    }
    public boolean deleteBook(long rowId){
        return mDb.delete(DATABASE_TABLE, KEY_ROWID + "=" + rowId, null) > 0;
    }
    public Cursor fetchAllBooks(){
        return mDb.query(DATABASE_TABLE, new String[]{KEY_BOOK, KEY_AUTHOR, KEY_ISBN, KEY_RATING}, null, null, null, null, null);
    }
    public Cursor fetchBook(long rowId) throws SQLException{
        Cursor mCursor =
        mDb.query(DATABASE_TABLE, new String[]{KEY_BOOK, KEY_AUTHOR, KEY_ISBN, KEY_RATING}, KEY_ROWID + "=" +
                                rowId, null, null, null, null);

        if(mCursor != null){
            mCursor.moveToFirst();
        }
        return mCursor;

    }
    public boolean updateBook(long rowId, String book, String author, String isbn, String rating){
        ContentValues args = new ContentValues();
        args.put(KEY_BOOK, book);
        args.put(KEY_AUTHOR, author);
        args.put(KEY_ISBN, isbn);
        args.put(KEY_RATING, rating);
        return mDb.update(DATABASE_TABLE, args, KEY_ROWID + "=" + rowId, null)> 0;
    }
}

Answer 1

啊，呃，很明显，你正在创建表DATABASE_TABLE，而不是collection。重构时，您必须错误地保留引号：

     "create table " + " DATABASE_TABLE " + " ("

Answer 2

private static final String DATABASE_CREATE =
                " create table " + " DATABASE_TABLE " + " ("
                + KEY_ROWID + " integer primary key autoincrement,      "
                + KEY_BOOK + " text not null, "
                + KEY_ISBN + " text not null, "
                + KEY_RATING + " text not null);";

我没有在您的数据库中看到“作者”列，您的意思是：

private static final String DATABASE_CREATE =
                " create table " + " DATABASE_TABLE " + " ("
                + KEY_ROWID + " integer primary key autoincrement,      "
                + KEY_BOOK + " text not null, "
                + KEY_ISBN + " text not null, "
                + KEY_AUTHOR + " text not null, "
                + KEY_RATING + " text not null);";

SQLite数据库列不存在错误

2 个答案: