Creating Tables: DDL for Python Devs
Map Python types to SQL types. Learn CREATE TABLE with primary keys, foreign keys, and constraints like NOT NULL and DEFAULT.
Sql
Window Functions: The Feature Python Developers Miss Most
Calculate across rows without collapsing them. Running totals, rankings, and row comparisons that GROUP BY can't do.
NULL: The Value That Isn't
NULL means unknown, not empty. Why NULL = NULL isn't true, three-valued logic, and how NULL behaves in WHERE, GROUP BY, JOINs and subqueries.
CTEs: Making Your SQL Readable
WITH clauses let you name your subqueries and read top-to-bottom instead of inside-out. Transform nested spaghetti into clean steps.
Subqueries: When SQL Needs Helper Functions
Nest queries inside queries, like Python helper functions. Use them in WHERE, SELECT, or FROM to compute intermediate results.
SQL Developer in 2026: Roles, Skills, and Career Path Explained
SQL is still heavily entrenched in corporate systems. No-SQL didn't kill it, and so far, AI hasn't killed it. I'm curious is SQL practitioners will become more...
JOINs Explained for Python Developers
Connect related tables like looking up values in a Python dictionary. Covers INNER JOIN, LEFT JOIN, and when to use each.
HAVING: Filtering Grouped Results
WHERE filters rows before grouping; HAVING filters after. Need "only cities with more than 10 customers"? That's HAVING.
GROUP BY: Aggregating Your Data
GROUP BY creates buckets and counts them. It's like Python's `collections.Counter` or pandas `groupby()`. Learn COUNT, SUM, AVG, MIN, and MAX.
WHERE: Filtering Your Data
Filter rows with conditions, the SQL equivalent of list comprehension `if` clauses. Covers AND/OR, IN, BETWEEN, LIKE patterns, and NULL handling.