1.返回数据库字段信息与要查询数据库的数据字段不一致：

如下例：返回的字段少个IMGURL

String where = String::format("%s='%s'",AppBean::APPID().string(),appid.string());
DbResolver* p = DbResolver::getInstance();
if (p != NULL) {
StringArray pro(2);
pro.replaceAt(AppBean::PACKAGENAME(),0);
pro.replaceAt(AppBean::APPNAME(),1);
AutoCursor cursor = p->query(AppBean::DOWNLOAD_TABLE_NAME(),pro,where,StringArray(0),"");
if (cursor->moveToFirst()) {
String pkg = cursor->getString(cursor->getColumnIndex(AppBean::PACKAGENAME()));
String appname = cursor->getString(cursor->getColumnIndex(AppBean::APPNAME()));
String imageUrl = cursor->getString(cursor->getColumnIndex(AppBean::IMGURL()));
Demand d = NotificationDelegate::createDemand(appname,pkg,imageUrl,"",NotificationDelegate::STATUS_WAITDOWNLOAD,NotificationDelegate::PARAM_CANCEL);
mpContext->invokeDelegate(&d);
}

}

正确方式应为：
String where = String::format("%s='%s'",appid.string());
DbResolver* p = DbResolver::getInstance();
if (p != NULL) {
StringArray pro(3);
pro.replaceAt(AppBean::PACKAGENAME(),1);
pro.replaceAt(AppBean::IMGURL(),2);
AutoCursor cursor = p->query(AppBean::DOWNLOAD_TABLE_NAME(),"");
if (cursor->moveToFirst()) {
String pkg = cursor->getString(cursor->getColumnIndex(AppBean::PACKAGENAME()));
String appname = cursor->getString(cursor->getColumnIndex(AppBean::APPNAME()));
String imageUrl = cursor->getString(cursor->getColumnIndex(AppBean::IMGURL()));
Demand d = NotificationDelegate::createDemand(appname,NotificationDelegate::PARAM_CANCEL);
mpContext->invokeDelegate(&d);
}
}