Test-driven development is something wonderful! Once you've established it in your organisation, you will start to: Greatly improve your quality (things break less often) Greatly improve your processes (things can be changed more easily) Greatly improve your developer atmosphere (things are more fun to do) The importance of doing the right test-driven development is to … Continue reading Easy Mocking of Your Database
Category: jooq-development
This category contains posts related to current developments of jOOQ
jOOQ’s Reason for Being
The below paragraphs were taken from the jOOQ preface from the manual. It is worth thinking about why you should (or should not) use jOOQ in a given project. Specifically, you might be choosing between jOOQ and JPA, jOOQ and Hibernate, or jOOQ and SLICK (in a Scala context). here's some guidance (slightly biased towards … Continue reading jOOQ’s Reason for Being
How to provide a good pull request
A jOOQ user just provided me with an awesome pull request. Check this out: What's so nice about this particular pull request: It has a couple of little refactoring steps It contains a little regression test Only at the end, it contains the actual fix This is really nice. With these many commits, I can … Continue reading How to provide a good pull request
The IS DISTINCT FROM predicate
The SQL-1999 standard specifies a useful IS DISTINCT FROM predicate, that behaves slightly different from the regular not equal comparison predicate. Here is its simple definition: 8.13 <distinct predicate> Format <distinct predicate> ::= <row value expression 3> IS DISTINCT FROM <row value expression 4> <row value expression 3> ::= <row value expression> <row value expression … Continue reading The IS DISTINCT FROM predicate
Funky String Function Simulation in SQLite
SQLite is so light, it doesn't have any useful string functions. It doesn't have ASCII(), LPAD(), RPAD(), REPEAT(), POSITION(), you name it. It does, however, have a wonderful RANDOMBLOB() function. So if you really need a good random number generator, use a SQLite database and generate a 1GB blob. That should give you a couple … Continue reading Funky String Function Simulation in SQLite
Simulation of TRUNC() in Derby
Derby is missing out a lot of functions from the set of functions that other databases usually provide. One example is the TRUNC(value, decimals) function. According to the Wikipedia, truncation can be achieved as such: -- trunc(x, n) CASE WHEN x > 0 THEN floor(power(10, n) * x) / power(10, n) ELSE ceil(power(10, n) * … Continue reading Simulation of TRUNC() in Derby
How to simulate MySQL’s INSERT statement extensions
I have previously posted about the SQL MERGE statement, and how powerful it is here: https://blog.jooq.org/arcane-magic-with-the-sql2003-merge-statement/ Unfortunately, not all databases support this statement. Also, very often it is quite a bit of overkill, when what you want to do is to simply INSERT or UPDATE a single record, depending on whether it already exists. MySQL's … Continue reading How to simulate MySQL’s INSERT statement extensions
jOOQ website re-launch
jOOQ has re-launched its website. Come back to see the new design here: https://www.jooq.org/
The Visitor Pattern Re-visited
The visitor pattern is one of the most overrated and yet underestimated patterns in object-oriented design. Overrated, because it is often chosen too quickly (possibly by an architecture astronaut), and then bloats an otherwise very simple design, when added in the wrong way. Underestimated, because it can be very powerful, if you don't follow the … Continue reading The Visitor Pattern Re-visited
Advanced SQL: Relational division in jOOQ
Relational algebra has its treats. One of the most academic features is the relational division. It is hardly ever used, but comes in handy every now and then. And when you need it, you'll probably hate yourself for having slept during the relevant classes at the university. What is relational division? Relational division is the … Continue reading Advanced SQL: Relational division in jOOQ