This section describes how you can use user defined functions (UDFs) in Exasol.
Introduction
User defined functions (UDFs) in Exasol allow you to program your own analysis, processing, and generation functions and to execute these functions in parallel inside an Exasol cluster. By using UDFs you can solve problems that are not possible to solve using only SQL statements.
What is the difference between UDFs and scripts in Exasol?
Scripts are limited to using the Exasol scripting language (Lua), whereas UDFs support several programming languages and can be used to run complex functions. A script is also a sequential program that only runs on a single cluster node, while UDFs are executed in parallel on all cluster nodes. This means that scripts are not suitable for processing result tables of SQL queries, since iterative operations on big data sets will be very time-consuming.
