The Guild Codex

What Is SQL Guild, Really?

This is the deep end — the guild's history, the full curriculum, and exactly how levels and scoring work. None of it is required reading before you play.

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The World

A Guild Built on Requests

SQL Guild is run out of a single guild hall, staffed by a small cast of adventurers, mages, and administrators who take on requests from clients across the region. At the front desk is Gillian — a 57-year-old elven mage who's spent decades keeping the guild's ledger straight and its newest recruits pointed in the right direction.

Every quest that comes through the door — protect, defeat, scout, obtain, infiltrate, hunt — gets logged: who issued it, what it requires, who's assigned, and whether it succeeded. That ledger is the actual database you'll be querying. Adventurers, creatures, items, skills, and the towns and dungeons they operate out of are all real rows in real tables, not flavor text sitting on top of a quiz.

Every level's dialogue happens inside this world, and every exercise is a real request answerable against that same guild ledger.

The Curriculum

What You'll Actually Learn

Levels and practice exercises are built against a 9-category map of SQL, ordered roughly beginner to advanced. Level 1 starts at category 1 — pure SELECT/WHERE/ORDER BY — before anything else gets introduced.

Querying & Filtering Basics

SELECT, WHERE, ORDER BY, and the filtering operators every query starts with.

Joins

Combine adventurers, quests, and locations across tables — inner, outer, and self joins.

Aggregation & Grouping

Summarize the guild's ledger with COUNT, SUM, AVG, and GROUP BY / HAVING.

Subqueries & Set Operations

Nest queries inside queries, and combine result sets with UNION, INTERSECT, and EXCEPT.

Conditional Logic, Functions & NULL Handling

CASE WHEN, COALESCE, string/date functions, and handling missing data cleanly.

CTEs & Window Functions

WITH clauses, recursive CTEs, and ranking/running totals with window functions.

Data Modification & Transactions

INSERT, UPDATE, DELETE, and keeping changes safe with transactions.

Schema Design, Constraints & Performance

Table design, constraints, indexes, views, and reading a query plan.

Advanced / Admin

Stored procedures, triggers, materialized views, JSON functions, and access control.

How It Works

Levels, Scoring, and Unlocking

Each level is built from a sequence of exercises, and each exercise is a request delivered through guild dialogue — a character asks for something, you write the query, and the game checks your result against what was actually asked for. Get it wrong and you get a hint drawn from that same dialogue system, not just a bare error message.

A level has a passing-criteria percentage — clear that bar and it's marked passed; clear it with a particularly strong run and it's marked excellent instead. Levels unlock in sequence, so you can't jump to a later level without having cleared the ones before it.

Practice mode uses this same scoring model for on-demand revision instead of a fixed story sequence — you choose the difficulty and quantity, or let it build a set from what you haven't mastered yet.

Ready to Put This Into Practice?

The Guild Board has the first levels open right now.

Go to the Guild Board