banDropDefault¶

Group destructive · Migrations only · Since Unreleased
Diagnostic lint/banDropDefault · Postgres error 23502

Sources: inspired by squawk/ban-drop-default

Description¶

Dropping a column or domain default may break existing clients.

Inserts that omit the column fail with 23502 not_null_violation if the column is NOT NULL, and silently write NULL otherwise.

Update your application code to provide a value for the column, then drop the default in a later migration.

Examples¶

Invalid¶

alter table users alter column created_at drop default;

code-block.sql:1:43 lint/banDropDefault ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ! Dropping the default of column created_at may break existing clients.

  > 1 │ alter table users alter column created_at drop default;
      │                                           ^^^^^^^^^^^^
    2 │ 

  i Inserts that omit the column fail if it is NOT NULL, and write NULL otherwise.

  i Update your application code to provide a value, then drop the default in a later migration.

alter domain status drop default;

code-block.sql:1:21 lint/banDropDefault ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ! Dropping the default of domain status may break existing clients.

  > 1 │ alter domain status drop default;
      │                     ^^^^^^^^^^^^
    2 │ 

  i Inserts that omit the column fail if it is NOT NULL, and write NULL otherwise.

  i Update your application code to provide a value, then drop the default in a later migration.

Valid¶

alter table users alter column created_at set default now();

How to configure¶

{
  "linter": {
    "rules": {
      "banDropDefault": "error"
    }
  }
}

How to suppress¶

Suppress this diagnostic with a comment:

-- pgls-ignore banDropDefault