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PYSPARK • LESSON 149

Registering SQL UDFs with spark.udf.register()

How do we register a Python function into the Spark SQL catalog so it can be called from spark.sql() queries?

Expert2 Minutes800 XP
🤔 THE QUESTION

How do we register a Python function into the Spark SQL catalog so it can be called from spark.sql() queries?

💡 WHAT IS IT?

spark.udf.register(name, func, returnType) publishes a Python UDF into the SQL expression engine.

🎯 WHAT IS IT USED FOR?

Allowing SQL analysts to execute custom Python business logic within standard SQL queries.

💻 EXAMPLE
spark.udf.register("sql_mask_email", mask_email, StringType())
spark.sql("SELECT sql_mask_email(email) FROM users").show()

🎯 Mission Objectives

Practice typing production-grade PySpark code for Registering SQL UDFs with spark.udf.register().

  • Register UDF in Spark SQL catalog
  • Call custom function in SQL SELECT query
  • Bridge Python functions to SQL