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Journey's end - Master of the Catalog

It is done, @name. You have reached the very summit of the Great Library of Alexandria. Look down at the road you have travelled.

Your journey through the Library

The Gate - you learned about databases, tables, rows and columns, and your first
```
SELECT
```
.
The Catalog Hall - you filtered (
```
WHERE
```
), sorted (
```
ORDER BY
```
) and limited results (
```
LIMIT
```
).
The Table Workshop - you created tables (
```
CREATE TABLE
```
) and added data (
```
INSERT
```
).
The Scriptorium - you changed and deleted data (
```
UPDATE
```
,
```
DELETE
```
).
The Great Halls - you linked shelves with joins (
```
JOIN
```
).
The Sages' Abacus - you grouped and counted (
```
GROUP BY
```
, aggregate functions).
The Chamber of Riddles - you delved into subqueries and
```
HAVING
```
.
The Vault of Speed - you sped up queries with indexes.
The Hall of Seals - you protected data with transactions and ordered it with views.

What's next, Master?

The Library never stops growing. If you wish to go further, here are your next scrolls:

Stored procedures - whole programs living inside the database.
Triggers (
TRIGGER
) - actions run automatically when data changes.
Normalization - the art of designing tables without repetition.
Query optimization - reading execution plans (
```
EXPLAIN
```
).
Other databases - PostgreSQL, as well as NoSQL databases like MongoDB.

Callimachus's final word

I created the Pinakes so that no scroll would be lost in the dark. You have learned the same art - to bring order to knowledge. Now go and build your own catalog. May your database stand as firm as the walls of Alexandria. You are a Master of the Catalog. THE TREASURY BELONGS TO YOU!

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