sqlite数据查询速度慢的可能原因

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'", AppBean::APPID().string(), appid.string());

DbResolver* p = DbResolver::getInstance();

if (p != NULL) {

StringArray pro(3);

pro.replaceAt(AppBean::PACKAGENAME(), 0);

pro.replaceAt(AppBean::APPNAME(), 1);

pro.replaceAt(AppBean::IMGURL(), 2);

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);

}

}