How to do in-query in jDBI?

问题:

How can I execute somethings like this in jDBI ?

@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)

Similar to @SelectProvider from myBatis.

Similar questions has been asked How do I create a Dynamic Sql Query at runtime using JDBI's Sql Object API?, but somehow answer is not clear to me.

回答1:

This should work:

@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:

@UseStringTemplate3StatementLocator

annotation (beacuse under the hood JDBI uses Apache StringTemplate to do such substitutions). 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).

回答2:

Use @Define annotation to build dynamic queries in jDBI. Example:

@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);

回答3:

With PostgreSQL, I was able to use the ANY comparison and bind the collection to an array to achieve this.

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.