Data science UDF examples

This section contains tutorials and examples that show how to use UDFs for data science.

The examples and tutorials in this section demonstrate the capabilities of UDFs in Exasol for data science purposes. In-depth knowledge of data science and the R and Python programming languages is not required to follow the tutorials.

The tutorials are designed to work with our free public demo system which contains pre-loaded data sets, but you can of course also use your own data sets in an existing Exasol deployment. The public demo system is a static shared system hosted in our own cloud and does not provide the full functionality of Exasol. To get access to the free public demo system, sign up here.

User defined functions (UDFs)

User defined functions (UDFs) allow you to program your own analysis, processing, or generation functions and to execute them in parallel within an Exasol cluster. There are different types of UDFs for different input and output specifications:

  INPUT

SCALAR

Single input

SET

Multiple rows as input

OUTPUT

RETURNS

Single output

Function:

Executed in parallel

Aggregation function:

Not executed in parallel except for GROUP BY

Examples:

my_maximum

json_value

Examples:

my_average

EMITS

Multiple output rows

 

Generator function / Map reduce / ETL UDFs:

Executed in parallel

Analytical function:

Not executed in parallel except for GROUP BY

Examples:

IMPORT_METADATA
(Cloud Storage Extension)

Examples:

IDA_TEST_MODEL
(Python classification tutorial)

FLIGHTS_PRED_DEP_DELAY
(R regression tutorial)

To learn more about how to use UDFs, see User defined functions (UDFs).

UDF tutorials

The following articles in this section contain a number of tutorials for different use cases:

  • Python classification tutorial

    Learn how UDFs can be used in a machine learning or data science context using Python. In this tutorial you will learn how to test the accuracy of a model, either from a SQL client or directly from your familiar Python environment such as Jupyter Notebooks.

  • R regression tutorial

    Learn how to display JSON data stored in a column as a table using a simple UDF.

  • Geocoding with UDFs

    Learn how to use Exasol to add geocodes to your data.