In a previous blog post, I wrote about why you should (almost) always default to using bind variables. There are some exceptions, which I will cover in another follow-up post, but by default, bind variables are the right choice, both from a performance and from a security perspective. In this article, I will show an … Continue reading When Using Bind Variables is not Enough: Dynamic IN Lists
Why SQL Bind Variables are Important for Performance
A common problem with dynamic SQL is parsing performance in production. What makes matters worse is that many developers do not have access to production environments, so they are unaware of the problem (even if there's nothing new about this topic). What exactly is the problem? Execution plan caches Most database vendors these days ship … Continue reading Why SQL Bind Variables are Important for Performance
Mocking JDBC Using a Set of SQL String / Result Pairs
In a previous blog post, I've shown how the programmatic MockDataProvider can be used to mock the entire JDBC API through a single functional interface: // context contains the SQL string and bind variables, etc. MockDataProvider provider = context -> { // This defines the update counts, result sets, etc. // depending on the context … Continue reading Mocking JDBC Using a Set of SQL String / Result Pairs
How to Compile a Class at Runtime with Java 8 and 9
In some cases, it's really useful to be able to compile a class at runtime using the java.compiler module. You can e.g. load a Java source file from the database, compile it on the fly, and execute its code as if it were part of your application. In the upcoming jOOR 0.9.8, this will be … Continue reading How to Compile a Class at Runtime with Java 8 and 9
A Completely Overhauled, Modularised jOOQ 3.11, Ready for Java 11
If you've been following the fast paced JDK 9+ projects, you may have noticed an exciting, first big change that has been made possible thanks to Java 9's Jigsaw feature. In JDK 11, JEP 320 will ship, or rather: it will no longer ship, as JEP 320 means that both CORBA and Java EE modules … Continue reading A Completely Overhauled, Modularised jOOQ 3.11, Ready for Java 11
Correct Reflective Access to Interface Default Methods in Java 8, 9, 10
When performing reflective access to default methods in Java, Google seems to fail us. The solutions presented on Stack Overflow, for instance, seem to work only in a certain set of cases, and not on all Java versions. This article will illustrate different approaches to calling interface default methods through reflection, as may be required … Continue reading Correct Reflective Access to Interface Default Methods in Java 8, 9, 10
Top 10 SQL Dialect Emulations Implemented in jOOQ
The SQL standard is a nice thing. But it's a standard. And as such, while it may provide good guidelines on how to implement some SQL features, most dialects deviate from it in one way or another (sometimes drastically, cheers, MySQL). But that doesn't have to be a bad thing. Innovation is not driven by … Continue reading Top 10 SQL Dialect Emulations Implemented in jOOQ
Map Reducing a Set of Values Into a Dynamic SQL UNION Query
Sounds fancy, right? But it's a really nice and reasonable approach to doing dynamic SQL with jOOQ. This blog post is inspired by a Stack Overflow question, where a user wanted to turn a set of values into a dynamic UNION query like this: SELECT T.COL1 FROM T WHERE T.COL2 = 'V1' UNION SELECT T.COL1 … Continue reading Map Reducing a Set of Values Into a Dynamic SQL UNION Query
How to Order Versioned File Names Semantically in Java
In most cases, natural sorting by sorting lexicographically is useful as a default in Java. This includes sorting file names, which are sorted lexicographically as well. However, when we have version numbers in our files (such as a set of SQL migration scripts), then we prefer the files to be sorted in a more intuitive … Continue reading How to Order Versioned File Names Semantically in Java
Type Safe Implicit JOIN Through Path Navigation in jOOQ 3.11
One of the biggest contributors to SQL syntax verbosity is the need to explicitly JOIN every table that somehow contributes to the query, even if that contribution is "trivial". When looking at the Sakila database, an example could be seen easily when fetching customer data: SELECT cu.first_name, cu.last_name, co.country FROM customer AS cu JOIN address … Continue reading Type Safe Implicit JOIN Through Path Navigation in jOOQ 3.11