Book Image

Spring Data

By : Petri Kainulainen
Book Image

Spring Data

By: Petri Kainulainen

Overview of this book

Spring Framework has always had a good support for different data access technologies. However, developers had to use technology-specific APIs, which often led to a situation where a lot of boilerplate code had to be written in order to implement even the simplest operations. Spring Data changed all this. Spring Data makes it easier to implement Spring-powered applications that use cloud-based storage services, NoSQL databases, map-reduce frameworks or relational databases. "Spring Data" is a practical guide that is full of step-by-step instructions and examples which ensure that you can start using the Java Persistence API and Redis in your applications without extra hassle. This book provides a brief introduction to the underlying data storage technologies, gives step-by-step instructions that will help you utilize the discussed technologies in your applications, and provides a solid foundation for expanding your knowledge beyond the concepts described in this book. You will learn an easier way to manage your entities and to create database queries with Spring Data JPA. This book also demonstrates how you can add custom functions to your repositories. You will also learn how to use the Redis key-value store as data storage and to use its other features for enhancing your applications. "Spring Data" includes all the practical instructions and examples that provide you with all the information you need to create JPA repositories with Spring Data JPA and to utilize the performance of Redis in your applications by using Spring Data Redis.
Table of Contents (13 chapters)

Sorting query results

In the course of this section, we will learn different techniques that can be used to sort query results with Spring Data JPA. We will also learn the guidelines that we can use to select a proper sorting method for each situation.

Sorting with method name

If we are building our queries by using the query generation from the method name strategy, we can sort query results by the following steps:

  1. Creating a query method

  2. Modifying an existing service method to use the new query method.

Creating the query method

When we are building our queries by using the query generation from the method name strategy, we can use the OrderBy keyword to sort the query results when we:

  1. Append the OrderBy keyword to the method name.

  2. Append the property expression that corresponds to the property of the entity, which is used to sort the query results, to the method name.

  3. Append a keyword describing the sorting order to the method name. If the query results are sorted in ascending order, the keyword...