Book Image

jOOQ Masterclass

By : Anghel Leonard
Book Image

jOOQ Masterclass

By: Anghel Leonard

Overview of this book

jOOQ is an excellent query builder framework that allows you to emulate database-specific SQL statements using a fluent, intuitive, and flexible DSL API. jOOQ is fully capable of handling the most complex SQL in more than 30 different database dialects. jOOQ Masterclass covers jOOQ from beginner to expert level using examples (for MySQL, PostgreSQL, SQL Server, and Oracle) that show you how jOOQ is a mature and complete solution for implementing the persistence layer. You’ll learn how to use jOOQ in Spring Boot apps as a replacement for SpringTemplate and Spring Data JPA. Next, you’ll unleash jOOQ type-safe queries and CRUD operations via jOOQ’s records, converters, bindings, types, mappers, multi-tenancy, logging, and testing. Later, the book shows you how to use jOOQ to exploit powerful SQL features such as UDTs, embeddable types, embedded keys, and more. As you progress, you’ll cover trending topics such as identifiers, batching, lazy loading, pagination, and HTTP long conversations. For implementation purposes, the jOOQ examples explained in this book are written in the Spring Boot context for Maven/Gradle against MySQL, Postgres, SQL Server, and Oracle. By the end of this book, you’ll be a jOOQ power user capable of integrating jOOQ in the most modern and sophisticated apps including enterprise apps, microservices, and so on.
Table of Contents (26 chapters)
1
Part 1: jOOQ as a Query Builder, SQL Executor, and Code Generator
4
Part 2: jOOQ and Queries
11
Part 3: jOOQ and More Queries
16
Part 4: jOOQ and Advanced SQL
22
Part 5: Fine-tuning jOOQ, Logging, and Testing

Casting, coercing, and collating

jOOQ was designed to handle most of the casting issues under the hood, including for ultra-strong-typed databases such as DB2. Nevertheless, explicit casting and/or coercing still serve some isolated cases. Most probably, we'll need them when we are not satisfied with the jOOQ automatic mapping (for instance, we consider that jOOQ didn't find the most accurate mapping), or we just need a certain type to respond to a special case. Even if they add a little bit of verbosity, casting and coercing can be used fluently; therefore, the DSL expressions are not disrupted.

Casting

Most of the time, jOOQ finds the most accurate data type mapping between the database and Java. If we look into a jOOQ generated class that mirrors a database table, then we see that, for each column that has a database-specific type (for example, VARCHAR), jOOQ has found a Java type correspondent (for example, String). If we compare the schema of the PAYMENT table...