With EXASOL 5 you can now write User-Defined Functions in Java – a new video shows you how.
EXASOL 5 now supports the use of Java as a programming language for User-Defined functions and I've produced a video describing the process of developing a Java UDF here.
In version 4, you could have used Lua, R or Python to achieve the same effect - but the advantage of supporting Java is that you may already have the Java code for many of the functions you would want to implement. In many cases, it's then a simple case of dropping this code into a Java UDF "template", saving a lot of development and testing effort.
We still support the other languages - it's partly a matter of personal taste which language you use - but in some cases Java is not the best tool for the job - for example R is often a better choice for complex statistical functions.
Additionally you can now "import" any of your custom libraries or any open source libraries into EXASOL for use with UDFs - for example the CRAN libraries for R
The upshot is that EXASOL 5 is more than just an excellent SQL. If something is difficult to say in SQL then maybe you can say it better in Java, Lua, R or Python.