The standard SQL WITH clause has been tremendously helpful in structuring SQL queries. Instead of nesting everything in unreadable derived tables like this: SELECT actor_id, name, COUNT(*) FROM ( SELECT actor_id, first_name || ' ' || last_name AS name FROM actor ) AS a JOIN film_actor AS fa USING (actor_id) GROUP BY actor_id, name ORDER … Continue reading LATERAL is Your Friend to Create Local Column Variables in SQL
Calling Procedures with Default Parameters using JDBC or jOOQ
Using jOOQ's code generator to call stored procedures is a popular reason to use jOOQ. For example, when you have a procedure like the following Oracle PL/SQL procedure: CREATE OR REPLACE PROCEDURE p ( p_i1 IN number, p_o1 OUT number, p_i2 IN varchar2, p_o2 OUT varchar2 ) IS BEGIN p_o1 := p_i1; p_o2 := p_i2; … Continue reading Calling Procedures with Default Parameters using JDBC or jOOQ
Using jOOQ’s Implicit Join From Within the JOIN .. ON Clause
Starting with jOOQ 3.11, type safe implicit JOIN have been made available, and they've been enhanced to be supported also in DML statements in jOOQ 3.17. Today, I'd like to focus on a somewhat weird but really powerful use-case for implicit JOIN, when joining additional tables from within an explicit JOIN's ON clause. The use … Continue reading Using jOOQ’s Implicit Join From Within the JOIN .. ON Clause
A Brief Overview over the Most Common jOOQ Types
For new users working with jOOQ for the first time, the number of types in the jOOQ API can be overwhelming. The SQL language doesn't have many such "visible" types, although if you think about SQL the way jOOQ does, then they're there just the same, but hidden from users via an English style syntax. … Continue reading A Brief Overview over the Most Common jOOQ Types
How to Plot an ASCII Bar Chart with SQL
No need for expensive Tableau subscriptions. Ditch Microsoft Excel. Just use native PostgreSQL to quickly visualise your data! Here's an idea I had for a while. As you may know, jOOQ can produce fancy charts from your jOOQ results. But that requires you use jOOQ, and you may not be using jOOQ, because you're not … Continue reading How to Plot an ASCII Bar Chart with SQL
The Second Best Way to Fetch a Spring Data JPA DTO Projection
I've just stumbled upon this great post by Vlad Mihalcea, titled The Best Way to Fetch a Spring Data JPA DTO Projection. It got some nice traction on reddit, too. This is such a nice use-case and apt solution, I wanted to quickly show the second best way of doing the same, with jOOQ this … Continue reading The Second Best Way to Fetch a Spring Data JPA DTO Projection
Cannot resolve symbol ‘VERSION_3_17’ in jOOQ generated code
Starting with jOOQ 3.16 and #12601, there may be a compilation error with a message like this in your jOOQ generated code: [ERROR] .../DefaultCatalog.java:[53,73] cannot find symbol[ERROR] symbol: variable VERSION_3_17[ERROR] location: class org.jooq.Constants Typically, this error is mixed with other compilation errors in generated code. Its purpose is to help troubleshoot these other compilation errors. … Continue reading Cannot resolve symbol ‘VERSION_3_17’ in jOOQ generated code
jOOQ 3.17 Supports Implicit Join also in DML
Since jOOQ 3.11, implicit joins have been supported. An implicit join is a JOIN (mostly a LEFT JOIN) that is generated implicitly because of the presence of a path expression. If SQL supported the syntax natively, it would look like this: SELECT cu.first_name, cu.last_name, cu.address.city.country.country FROM customer AS cu All that is is convenience for … Continue reading jOOQ 3.17 Supports Implicit Join also in DML
A Condition is a Field
Starting with jOOQ 3.17, the Condition type extends the Field<Boolean> type. Because, that's what the SQL standard thinks it is, in sorts: <boolean value expression> ::= <predicate> The exact definition contains intermediate rules, but you get the idea. A <predicate> (which is a Condition in jOOQ) can be used wherever a <boolean value expression> can … Continue reading A Condition is a Field
The Many Ways to Return Data From SQL DML
Probably the hardest thing to standardise in SQL is RETURNING data from DML statements. In this article, we'll look at various ways of doing that with jOOQ, in many of jOOQ's supported dialects, and with JDBC directly. How to do it with jOOQ Assuming the usual table from the sakila database: CREATE TABLE actor ( … Continue reading The Many Ways to Return Data From SQL DML