load

关于Hibernate的load和get方法的区别，网上一抓一大片。不过，也许是版本的不同，感觉网上的文章有其谬误。况且，说两者区别的文章一大片，但几近没有文章谈及何时使用这两方法合适。 网上流传较广的说法之一是：load比get效率高。 理由是：load比较聪明，会先从1、2级缓存中找数据，找不到再从数据库中查询；而get则是个笨蛋，不管三七二十一，直接查数据库。 也许老版本是这样，实际上，我用Hibernate3.6测试发现，get也会从缓存中找数据。所以，在查询方面，我认为两者间的效率并无甚差异——想想也该明白，如果load真比get全方位的优胜，那get还有存在的意义么？早就被Hibernate开发组的人淘汰了。 那么，load和get到底有什么区别——或者说，他们各自应用在什么地方？ 我觉得，他们俩之间的关系就像是单例模式中的懒汉式和饿汉式——如果要取的数据不多，并且确定一定会用到，那么直接拿过来就好；反过来，如果要查的数据不一定被用到，而且数据量较大，耗费资源较多，那我们就应该使用load延迟加载，即在真正要用的时候再来查询数据。 网上的文章大多都列了好多load和get的不同之处的条目，这里就不再赘述了——优秀的程序员从不干重复低价值的劳动，嘿嘿。 来源： oschina 链接： https://my.oschina.net/u/1379006/blog/190094

版权声明 ：转载时请以超链接形式标明文章原始出处和作者信息及 本声明 http://www.blogbus.com/fallenlord-logs/57543854.html 最近面试别人，正好出的笔试题中有道关于Hibernate延迟加载的问题，聊天过程中发现很多人对Hibernate的延迟加载有些理解误区，写些东东在这里，希望对大家有所帮助。 首先是第一个误区： 延迟加载只能作用于关联实体 看到这个是不是在想：非关联实体延迟加载有什么用？ 为了解答上面这个问题，我们可以先考虑另一个问题： Hibernate Session的get和load方法有什么区别？ 如果你的回答是： 当方法参数为数据库不存在的id时，get会返回null，load会抛出异常 ，那么恭喜你，进入了第二个误区 如果此时你还想补充一下： load会从缓存中取出数据而get不会 ，再次恭喜，进入第三个误区 如果你在上面三个误区中有一个踏入了，那么我敢打赌，你一定是被网上那些半吊子的工程师们写的博客给戕害了。。。。 此时是不是很愤怒？这些长久以来你牢记在心的Hibernate的特性原来都是浮云。。。。 呵呵，接下来我们一个个来走出这些误区。 Mop上无图无真相，我们这里无码无真相——不要误会，我是说代码 首先看看第二个误区：当方法参数为数据库不存在的id时，get会返回null，load会抛出异常 如果你现在想说

I need to get the title of a remote page by URL. The code works in FFX, but not chrome. Anyone have any ideas? $(document).ready(function(){ $("title").remove(); $("head").load("http://www.latentmotion.com title"); }); Here, this works in all browsers $.get("http://www.latentmotion.com", function(response){ alert((/<title>(.*?)<\/title>/m).exec(response)[1]); }); You can test it here http://jsfiddle.net/N7D5r/ And if you want to avoid jQuery altogether var getXhr = (function () { if ("XMLHttpRequest" in window) { return function () { return new XMLHttpRequest(); }; } else { var item =

I've got a problem with my FB apps with Internet Explorer 7. I'm using this piece of code, provided by FB some time ago : $auth_url = "http://www.facebook.com/dialog/oauth?client_id=" . FACEBOOK_APP_ID . "&redirect_uri=" . urlencode(CANVAS_PAGE . 'index.php') . "&scope=user_likes,publish_stream"; $signed_request = $_REQUEST["signed_request"]; list($encoded_sig, $payload) = explode('.', $signed_request, 2); $data = json_decode(base64_decode(strtr($payload, '-_', '+/')), true); // If first time we use the application -> ask for permissions if (empty($data["user_id"])) { echo("<script> top

In order to optimize the load of my document, I use to load jquery async like that <script async type="text/javascript" src="js/jquery-1.12.3.min.js"></script> Then I call a script using jquery : <script type="text/javascript"> jQuery(document).ready(function() { App.init(); OwlCarousel.initOwlCarousel(); FancyBox.initFancybox(); StyleSwitcher.initStyleSwitcher(); }); </script> It returns me that jquery is not defined. I don't know what should I use, I though that .readyfunction would wait untill all document is loaded before calling it. the same for boostrap library, It tells me that jquery

I have an issue when I go from viewController A to viewController B, in which it has roughly a 5 second delay before segueing to it. I believe it is due to the amount of views that I'm loading up in viewDidLoad. I have an xib file that has a stack view of 11 sections that represent levels. Each section has a button and a few images that can change depending on the users progress. In addition, I instantiate 10 of these xib views to load in a scrollview. This all happens in the viewDidLoad. I'm wondering if I can load viewController B and have it all ready to go before actually clicking the

I'm migrating from MATLAB to ipython and before taking the leap I'm going through my minimal workflow to make sure every operation I perform daily on MATLAB for data crunching is available on ipython. I'm currently stuck on the very basic task of saving and loading numpy arrays via a one-line command, such as MATLAB's: >>> save('myresults.mat','a','b','c') >>> load('myresults.mat') In particular, what I like about MATLAB's load command is that not only it reads the data file but it loads the variables into the workspace, nothing else is needed to start working with them. Note that this is not