On snakes and elephants Using Python inside PostgreSQL Jan Urba´nski
[email protected] New Relic PyWaw Summit 2015, Warsaw, May 26 Jan Urba´nski (New Relic) On snakes and elephants PyWaw Summit 1 / 32 For those following at home Getting the slides $ wget http://wulczer.org/pywaw-summit.pdf Jan Urba´nski (New Relic) On snakes and elephants PyWaw Summit 2 / 32 1 Introduction Stored procedures PostgreSQL's specifics 2 The PL/Python language Implementation Examples 3 Using PL/Python Real-life applications Best practices Jan Urba´nski (New Relic) On snakes and elephants PyWaw Summit 3 / 32 Outline 1 Introduction Stored procedures PostgreSQL's specifics 2 The PL/Python language 3 Using PL/Python Jan Urba´nski (New Relic) On snakes and elephants PyWaw Summit 4 / 32 What are stored procedures I procedural code callable from SQL I used to implement operations that are not easily expressed in SQL I encapsulate business logic Jan Urba´nski (New Relic) On snakes and elephants PyWaw Summit 5 / 32 Stored procedure examples Calling stored procedures SELECT purge_user_records(142); SELECT lower(username) FROM users; CREATE TRIGGER notify_user_trig AFTER UPDATEON users EXECUTE PROCEDURE notify_user(); Jan Urba´nski (New Relic) On snakes and elephants PyWaw Summit 6 / 32 Stored procedure languages I most RDBMS have one blessed language in which stored procedures can we written I Oracle has PL/SQL I MS SQL Server has T-SQL I but Postgres is better Jan Urba´nski (New Relic) On snakes and elephants PyWaw Summit 7 / 32 Stored procedures in Postgres I a stored