For the latest stable version, please use Spring Data Redis 3.4.0! |
Redis-specific Query Methods
Query methods allow automatic derivation of simple finder queries from the method name, as shown in the following example:
public interface PersonRepository extends CrudRepository<Person, String> {
List<Person> findByFirstname(String firstname);
}
Please make sure properties used in finder methods are set up for indexing. |
Query methods for Redis repositories support only queries for entities and collections of entities with paging. |
Using derived query methods might not always be sufficient to model the queries to run. RedisCallback
offers more control over the actual matching of index structures or even custom indexes.
To do so, provide a RedisCallback
that returns a single or Iterable
set of id
values, as shown in the following example:
String user = //...
List<RedisSession> sessionsByUser = template.find(new RedisCallback<Set<byte[]>>() {
public Set<byte[]> doInRedis(RedisConnection connection) throws DataAccessException {
return connection
.sMembers("sessions:securityContext.authentication.principal.username:" + user);
}}, RedisSession.class);
The following table provides an overview of the keywords supported for Redis and what a method containing that keyword essentially translates to:
Keyword | Sample | Redis snippet |
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Sorting Query Method results
Redis repositories allow various approaches to define sorting order.
Redis itself does not support in-flight sorting when retrieving hashes or sets.
Therefore, Redis repository query methods construct a Comparator
that is applied to the result before returning results as List
.
Let’s take a look at the following example:
interface PersonRepository extends RedisRepository<Person, String> {
List<Person> findByFirstnameOrderByAgeDesc(String firstname); (1)
List<Person> findByFirstname(String firstname, Sort sort); (2)
}
1 | Static sorting derived from method name. |
2 | Dynamic sorting using a method argument. |