Question

我正在利用Hibernate spoint Query执行一个储存程序,归还一个庞大的数据集(200多万行)。亚洲开发银行是Oracle 11g。

for instance: Query query = session.getNamedQuery(procName);

I know from the hibernate documentation, you cannot use setFirstResult/setMaxResult as stated on http://docs.jboss.org/hibernate/core/3.3/reference/en/html/querysql.html.

整个数据集,如100 000字。然而,一旦我用1 000 000 000 000美元进行测试,我就会发现外部错误。

从问答题看,我收到了一份名单。我假定,数据仅一字不提,一字不提(<代码>query.list(>)。

I do not have a 2nd level cache configured. Will these settings help at all, when dealing with an Oracle Stored Procedure.

query.setCacheMode(org.hibernate.CacheMode.IGNORE); query.setFetchSize(1000); query.scroll(org.hibernate.ScrollMode.FORWARD_ONLY);

基本上,我如何利用在Hibernate储存的代用品管理大型数据集检索。

百万美元

Answer 1

这完全取决于你如何处理从询问中获得的数据。如果你把它当作典型的问话题,即把它列入名单,并将结果储存起来,你会把你的记忆限制与这么多的几行相 bus。关键是要把他们带入并处理。 http://docs.jboss.org/hibernate/core/3.5/javadocs/org/hibernate/ScrollableResults.html 届会自作为第一层切身起,将储存所有装载物体。看一下Hibernate的批量处理情况,但需小心不要与Hibernate s batch fetching 和相关概念混淆。这些动物有两种不同的动物。

Answer 2

Your issue is less one of Hibernate than one of memory usage. I had a similar situation where a JMS message worked fine with a small amount of data, then everything blew up with more. Since I doubt you need all 2mm records in memory at once, see if you can get the stored proc updated to take a limit and an offset so that it can return slices of data as opposed to only the whole dataset.

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