How do we register a Python function into the Spark SQL catalog so it can be called from spark.sql() queries?
spark.udf.register(name, func, returnType) publishes a Python UDF into the SQL expression engine.
Allowing SQL analysts to execute custom Python business logic within standard SQL queries.
spark.udf.register("sql_mask_email", mask_email, StringType())
spark.sql("SELECT sql_mask_email(email) FROM users").show()Practice typing production-grade PySpark code for Registering SQL UDFs with spark.udf.register().