SQLite Android内连接

Select 
    F._id,F.id,F.logo,F.total_like,F.distance,F.store_name,F.mob_no_1,F.mob_no_2,F.mob_no_3,F.tel_no_1,F.tel_no_2,F.tel_no_3,F.description,R.total_record,R.total_page,R.current_page 
from 
    FAVOURITE_STORES as F 
    INNER JOIN FAVOURITE_RECORDS as R on F.area_id = R.area_id 
where 
    F.area_id = 2 and 
    R.area_id = 2

我在某些设备上将光标计数设置为1,在某些设备上,我将光标计数设置为零.即使表格中有数据.

这是我的选择查询功能

public Cursor rawQuery(String sQuery,String[] selectionArgs) {
        if(mDatabase == null) {
            mDatabase = getWritableDatabase();
        }
        debug("Query "+sQuery);
        return mDatabase.rawQuery(sQuery,selectionArgs);
    }

游标类

public class ExampleCursorLoader extends CursorLoader {
    private Activity mActivity;
    private String msQuery;
    private DBUtil mDbUtil;
    private String[] mSelectionArgs;

    public ExampleCursorLoader(Activity context,String query,String[] selectionArgs) {
        super(context);
        this.mActivity = context;
        this.msQuery = query;
        this.mSelectionArgs = selectionArgs;
        this.mDbUtil = DBUtil.getInstance(mActivity.getApplicationContext());
    }

    public ExampleCursorLoader(Activity context,String query) {
        this(context,query,null);
        debug(query);
    }
    public Cursor loadInBackground() {  
        debug("Loading in Background");
        Cursor cursor=null;
        cursor = mDbUtil.rawQuery(msQuery,mSelectionArgs);
        return cursor;
    }

    private void debug(String s) {
        Log.v("Adapter ","Adapter " + s);
    }

    protected void onStartLoading() {
        forceLoad();
        debug("Started Loading");
    }

    protected void onStopLoading() {
        super.onStopLoading();
    }


}

这就是我所说的.

return new ExampleCursorLoader(mActivity,sQuery);

计数为1的设备是三星s3.三星是Grand.
有什么想法或建议吗？

解决方法

Device that gives count as 1 is Samsung s3. And zero is Samsung Grand.
Have any thought or suggestion on this?

这种问题很难解释,因为它很可能不会抛出任何错误,只会显示不同的和不需要的结果.

您所能做的就是“改进查询”：

首先使用占位符而不是原始语句：

String query = "... where F.area_id = ? and R.area_id = ?";
String[] whereArgs = {"2","2"};

你也不需要使用AS子句,这足以说：

... from FAVOURITE_STORES F INNER JOIN FAVOURITE_RECORDS R on ...

从您提供的代码看起来是正确的(查询和rawQuery()的用法).

（编辑：李大同）

【声明】本站内容均来自网络，其相关言论仅代表作者个人观点，不代表本站立场。若无意侵犯到您的权利，请及时与联系站长删除相关内容!