Amazon Redshift will no longer support the creation of new Python UDFs starting Patch 198. Existing Python UDFs will continue to function until June 30, 2026. For more information, see the [ blog post ](https://amazonaws-china.com/blogs/big-data/amazon-redshift-python-user-defined-functions-will-reach-end-of-support-after-june-30-2026/). 

# SQL reference conventions
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This section explains the conventions that are used to write the syntax for the SQL expressions, commands, and functions described in the SQL reference section. 

[\[See the AWS documentation website for more details\]](http://docs.amazonaws.cn/en_us/redshift/latest/dg/c_SQL_reference_conventions.html)