开源Java库的SQL实用程序功能？

Question

我正在寻找一个SQL实用程序库，该库允许我执行以下操作：使用LIKE转义字符串以进行前缀搜索，或者通过添加术语（带有占位符支持）以编程方式编写查询的WHERE部分。

Answer 1

Projects like Quaere , LIQUidFORM , jaQu , JEQUEL (Java Embedded QUEry Language) all offer a fluent interface to write SQL statements and might be what you're looking for. For example, with JEQUEL:

public void testParameterExample() {
    final Sql sql = select(ARTICLE.NAME, ARTICLE.ARTICLE_NO)
            .from(ARTICLE)
            .where(ARTICLE.OID.in(named("article_oid"))).toSql();
    assertEquals("select ARTICLE.NAME, ARTICLE.ARTICLE_NO from ARTICLE where ARTICLE.OID in (:article_oid)", sql.toString());

    final Collection<String> articleDesc = sql.executeOn(dataSource)
            .withParams("article_oid", Arrays.asList(10, 11, 12))
            .mapBeans(new BeanRowMapper<ArticleBean, String>() {
                public String mapBean(final ArticleBean bean) {
                    return bean.getArticleNo() + "/" + bean.getName();
                }
            });
    assertEquals(1, articleDesc.size());
    assertEquals("12345/Foobar", articleDesc.iterator().next());
}

More of them at the bottom of the jaQu webpage.

Answer 2

A typical ORM framework like hibernate or JPA provides this out of the box.

eg in hibernate .

from Document doc fetch all properties where lower(doc.name) like 'cats%'

will return Document object where the nqme start with cats.

For parameter queries :

Query q = s.createQuery("from foo Foo as foo where foo.name=:name and foo.size=:size");
q.setProperties(fooBean); // fooBean has getName() and getSize()
List foos = q.list();

It will also save you from a lot of boilerplate to create all the JDBC objects needed and all the error handling.

If you need to stay close to SQL, give iBatis a careful look.

Answer 3

If you're still thinking about SQL in these low-level terms, I'd say you aren't being object-oriented enough.

Think about your problems in terms of objects. You're still too mired in the primitive level.

Consider better abstractions for persistence on top of your model objects: the DAO pattern, Spring JDBC, iBatis, ORM tools like Hibernate, etc.