JPA CriteriaQuery: getCount + condition

Question

我尝试获取所有未分析的文章（文章.class）计数（分析==错误）。可悲的是，以下代码返回绝对错误的数字。有人知道为什么吗？

CriteriaBuilder cb = entityManager.getCriteriaBuilder();
CriteriaQuery<Long> query = cb.createQuery(Long.class);
query.select(cb.count(query.from(Article.class)));
Root<Article> articles = query.from(Article.class);
Predicate condition = cb.isFalse(articles.get(Article_.analyzed));
query.where(condition);
TypedQuery<Long> unanalyzedArticlesAmount = entityManager.createQuery(query);
return unanalyzedArticlesAmount.getSingleResult();

Answer 1

终于读到了这篇文章：如何在通用JPA DAO中计算JPA 2 CriteriaQuery的行数？

并找到了以下解决方案：

CriteriaBuilder cb = entityManager.getCriteriaBuilder();
CriteriaQuery query = cb.createQuery();    
Root<Article> root = query.from(Article.class);
query.select(cb.count(root));
Predicate condition = cb.isFalse(root.get(Article_.analyzed));
query.where(condition);
TypedQuery<Long> unanalyzedArticlesAmount = entityManager.createQuery(query);
return unanalyzedArticlesAmount.getSingleResult();