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如何在jDBI中进行查询?

[英]How to do in-query in jDBI?

How can I execute somethings like this in jDBI ? 如何在jDBI中执行这样的事情?

@SqlQuery("select id from foo where name in <list of names here>")
List<Integer> getIds(@Bind("nameList") List<String> nameList);

Table: foo(id int,name varchar) 表: foo(id int,name varchar)

Similar to @SelectProvider from myBatis. 与myBatis的@SelectProvider类似。

Similar questions has been asked How do I create a Dynamic Sql Query at runtime using JDBI's Sql Object API? 类似的问题已经被问到如何使用JDBI的Sql Object API在运行时创建动态Sql查询? , but somehow answer is not clear to me. ,但不知何故,答案对我来说并不清楚。

This should work: 这应该工作:

@SqlQuery("select id from foo where name in (<nameList>)")
List<Integer> getIds(@BindIn("nameList") List<String> nameList);

Don't forget to annotate class containing this method with: 不要忘记使用以下方法注释包含此方法的类:

@UseStringTemplate3StatementLocator

annotation (beacuse under the hood JDBI uses Apache StringTemplate to do such substitutions). 注释(因为引擎盖JDBI使用Apache StringTemplate进行此类替换)。 Also note that with this annotation, you cannot use '<' character in your SQL queries without escaping (beacause it is a special symbol used by StringTemplate). 另请注意,使用此注释时,不能在不进行转义的情况下在SQL查询中使用“<”字符(因为它是StringTemplate使用的特殊符号)。

Use @Define annotation to build dynamic queries in jDBI. 使用@Define批注在jDBI中构建动态查询。 Example: 例:

@SqlUpdate("insert into <table> (id, name) values (:id, :name)")
public void insert(@Define("table") String table, @BindBean Something s);

@SqlQuery("select id, name from <table> where id = :id")
public Something findById(@Define("table") String table, @Bind("id") Long id);

With PostgreSQL, I was able to use the ANY comparison and bind the collection to an array to achieve this. 使用PostgreSQL,我能够使用ANY比较并将集合绑定到数组来实现这一目标。

public interface Foo {
    @SqlQuery("SELECT id FROM foo WHERE name = ANY (:nameList)")
    List<Integer> getIds(@BindStringList("nameList") List<String> nameList);
}

@BindingAnnotation(BindStringList.BindFactory.class)
@Retention(RetentionPolicy.RUNTIME)
@Target({ElementType.PARAMETER})
public @interface BindStringList {
    String value() default "it";

    class BindFactory implements BinderFactory {
        @Override
        public Binder build(Annotation annotation) {
            return new Binder<BindStringList, Collection<String>>() {
                @Override
                public void bind(SQLStatement<?> q, BindStringList bind, Collection<String> arg) {
                    try {
                        Array array = q.getContext().getConnection().createArrayOf("varchar", arg.toArray());
                        q.bindBySqlType(bind.value(), array, Types.ARRAY);
                    } catch (SQLException e) {
                        // handle error
                    }
                }
            };
        }
    }
}

NB: ANY is not part of the ANSI SQL standard, so this creates a hard dependency on PostgreSQL. 注意:ANY不是ANSI SQL标准的一部分,因此这会对PostgreSQL产生硬依赖。

If you are using the JDBI 3 Fluent API, you can use bindList() with an attribute: 如果您使用的是JDBI 3 Fluent API,则可以将bindList()与属性一起使用:

List<String> keys = new ArrayList<String>()
keys.add("user_name");
keys.add("street");

handle.createQuery("SELECT value FROM items WHERE kind in (<listOfKinds>)")
      .bindList("listOfKinds", keys)
      .mapTo(String.class)
      .list();

// Or, using the 'vararg' definition
handle.createQuery("SELECT value FROM items WHERE kind in (<varargListOfKinds>)")
      .bindList("varargListOfKinds", "user_name", "docs", "street", "library")
      .mapTo(String.class)
      .list();

Note how the query string uses <listOfKinds> instead of the usual :listOfKinds . 请注意查询字符串如何使用<listOfKinds>而不是通常的:listOfKinds

Documentation is here: http://jdbi.org/#_binding_arguments 文档在这里: http//jdbi.org/#_binding_arguments

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