Web Dev//SQL//DDL

Data Definition Language — the subset of SQL that defines structure, not data. `CREATE TABLE`, `ALTER TABLE`, `DROP TABLE`. Building the container, not filling it.

Data Definition Language — the subset of SQL that defines structure, not data. CREATE TABLE, ALTER TABLE, DROP TABLE. Building the container, not filling it.

Creating a table with 20 columns is 42 clean lines. SQL is the most optimal way to define big entities — evolutionarily elegant.

Key constraints in a CREATE TABLE: UUID PRIMARY KEY DEFAULT gen_random_uuid() — unique identifier per row, auto-generated if not provided

NOT NULL — mandatory field

REFERENCES tabla(columna) — foreign key, points to another table

DEFAULT valor — fallback value

CHECK (col IN (...)) — only accepts these values (like an enum)

UNIQUE (a, b) — the combination can't repeat

TEXT[] — array inside a column (PostgreSQL specific)

In Supabase, you write DDL in the SQL Editor, not the Table Editor. The Table Editor is for viewing and editing rows (spreadsheet mode). The SQL Editor can do everything — triggers, indexes, RLS policies, complex queries. One is visual, the other is powerful. The SQL Editor even lets you save queries as favorites — that's the kind of thing that makes you go "oh NICE."