postgresql/no-volatile-default-on-add-column

Why this matters

PG10+ has a stable-default short-cut: `ADD COLUMN ... DEFAULT <constant or STABLE>` does not rewrite the table. A `VOLATILE` default forces a full table rewrite under `ACCESS EXCLUSIVE`. The rule curates the volatile-function list — `random`, `gen_random_uuid`, `uuid_generate_v1*`, `uuid_generate_v4`, `clock_timestamp`, `timeofday`. STABLE defaults like `now()` / `current_timestamp` are not flagged. One layer of `TypeCast` is unwrapped so `gen_random_uuid()::uuid` is detected.

Examples

ALTER TABLE t ADD COLUMN x integer DEFAULT random();

ALTER TABLE t ADD COLUMN id uuid DEFAULT gen_random_uuid();

ALTER TABLE t ADD COLUMN x integer DEFAULT 1;

ALTER TABLE t ADD COLUMN z timestamptz DEFAULT now();

ALTER TABLE t ADD COLUMN id integer; -- no default at all is fine

Configure it

// eslint.config.js
import postgresql from "eslint-plugin-postgresql";

export default [
  {
    files: ["**/*.sql"],
    languageOptions: {
      parser: postgresql.configs.recommended.languageOptions.parser,
    },
    plugins: { postgresql },
    rules: {
      "postgresql/no-volatile-default-on-add-column": "error",
    },
  },
];

Options

This rule has no options.