Using H2 as a Test Database Product with jOOQ

The H2 database is an immensely popular in-memory database product mostly used by Java developers for testing. If you check out the DB-Engines ranking, it ranks 50th, which is quite impressive, as this rank outperforms products like: CockroachDBIgniteSingle Store (previously MemSQL)Interbase (which was forked as Firebird)Ingres (which is a predecessor to the awesome PostgreSQL)Google BigTable … Continue reading Using H2 as a Test Database Product with jOOQ

The Best Way to Call Stored Procedures from Java: With jOOQ

jOOQ is mainly known for its powerful type safe, embedded, dynamic SQL capabilities that are made available through code generation. However, a secondary use case of code generation is to use it for stored procedures (possibly exclusively for stored procedures). Stored procedures are powerful ways of moving complex data processing logic to the server. This … Continue reading The Best Way to Call Stored Procedures from Java: With jOOQ

Create Dynamic Views with jOOQ 3.17’s new Virtual Client Side Computed Columns

One of jOOQ 3.17's coolest new features are client side computed columns. jOOQ 3.16 already added support for server side computed columns, which many of you appreciate for various reasons. What's a computed column? A computed column is a column that is derived ("computed") from an expression. It cannot be written to. It works like … Continue reading Create Dynamic Views with jOOQ 3.17’s new Virtual Client Side Computed Columns

3.17.0 Release with Computed Columns, Audit Columns, Pattern Matching, Reactive Transactions and Kotlin Coroutine Support

This release contiues the work from previous releases around more sophisticated SQL transformation capabilities, including: Client side computed columns for both read and write operationsAudit columnsPattern matching SQL transformationsMore implicit JOIN capabilities Client side computed columns A ground breaking new core feature available in all commercial distributions isthe new client side computed columns feature, building … Continue reading 3.17.0 Release with Computed Columns, Audit Columns, Pattern Matching, Reactive Transactions and Kotlin Coroutine Support

How to Filter a SQL Nested Collection by a Value

I stumbled upon a very interesting question on Stack Overflow about how to use jOOQ's MULTISET operator to nest a collection, and then filter the result by whether that nested collection contains a value. The question is jOOQ specific, but imagine, you have a query that nests collections using JSON in PostgreSQL. Assuming, as always, … Continue reading How to Filter a SQL Nested Collection by a Value

The Performance of Various To-Many Nesting Algorithms

It's been a while since jOOQ 3.15 has been released with its revolutionary standard SQL MULTISET emulation feature. A thing that has been long overdue and which I promised on twitter a few times is to run a few benchmarks comparing the performance of various approaches to nesting to-many relationships with jOOQ. This article will … Continue reading The Performance of Various To-Many Nesting Algorithms

Changing SELECT .. FROM Into FROM .. SELECT Does Not “Fix” SQL

Every now and then, I see folks lament the SQL syntax's peculiar disconnect between the lexical order of operations (SELECT .. FROM) the logical order of operations (FROM .. SELECT) Most recently here in a Youtube comment reply to a recent jOOQ/kotlin talk. Let's look at why jOOQ didn't fall into this trap of trying … Continue reading Changing SELECT .. FROM Into FROM .. SELECT Does Not “Fix” SQL

The Many Different Ways to Fetch Data in jOOQ

The jOOQ API is all about convenience, and as such, an important operation (the most important one?) like fetch() must come with convenience, too. The default way to fetch data is this: Result<Record1<String>> result = ctx.select(BOOK.TITLE) .from(BOOK) .fetch(); for (Record1<String> record : result) { // ... } It fetches the entire result set into memory … Continue reading The Many Different Ways to Fetch Data in jOOQ

Setting the JDBC Statement.setFetchSize() to 1 for Single Row Queries

An interesting hint by Vladimir Sitnikov has made me think about a new benchmark for jOOQ: https://twitter.com/lukaseder/status/1407662449331949568 The benchmark should check whether single row queries should have a JDBC Statement.setFetchSize(1) call made to them by default. The Javadoc of the method says: Gives the JDBC driver a hint as to the number of rows that … Continue reading Setting the JDBC Statement.setFetchSize() to 1 for Single Row Queries

How to Typesafely Map a Nested SQL Collection into a Nested Java Map with jOOQ

A really cool, recent question on Stack Overflow was about how to map a nested collection into a Java Map with jOOQ. In the past, I've blogged about the powerful MULTISET operator many times, which allows for nesting collections in jOOQ. This time, instead of nesting data into a List<UserType>, why not nest it in … Continue reading How to Typesafely Map a Nested SQL Collection into a Nested Java Map with jOOQ