parameters:
  operation:
    type: string
    required: true
    enum: [create_table, add_constraint, select_type, design_schema]
  table_name:
    type: string
    pattern: "^[a-z][a-z0-9_]*$"
  schema:
    type: string
    default: "public"

CREATE TABLE schema_name.table_name (
    id BIGINT GENERATED ALWAYS AS IDENTITY PRIMARY KEY,
    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
);

-- Foreign key
CONSTRAINT fk_name FOREIGN KEY (col) REFERENCES other(id) ON DELETE CASCADE;
-- Check
CONSTRAINT chk_positive CHECK (amount > 0);
-- Unique
CONSTRAINT uq_email UNIQUE (email);

DO $$ BEGIN
    DROP TABLE IF EXISTS test_users;
    CREATE TABLE test_users (id BIGINT GENERATED ALWAYS AS IDENTITY PRIMARY KEY);
    ASSERT EXISTS (SELECT 1 FROM information_schema.tables WHERE table_name = 'test_users');
    DROP TABLE test_users;
END $$;

Skill("postgresql-fundamentals")