Complex joins

Applying SQL to Real-World Problems

Dmitriy (Dima) Gorenshteyn

Lead Data Scientist, Memorial Sloan Kettering Cancer Center

A complex question

popcorn

rental table

next table to be selected

rental table and address table

the missing table connecting rental and address

completed entity relationship diagram

-- LIMIT your results
SELECT * 
FROM ___ 
LIMIT 10;

-- List the tables you have
SELECT * 
FROM pg_catalog.pg_tables
WHERE schemaname = 'public';

-- Explore tables & columns using your new VIEW
SELECT * FROM table_columns;

Applying SQL to Real-World Problems