W14 Adding a primary key using an index
Description
Triggered when: A primary key was added using an index on the table.
Effect: This can cause postgres to alter the index columns to be NOT NULL.
Workaround: Make sure that all the columns in the index are already NOT NULL.
Detected by: eugene lint
Problematic migration
-- 1.sql
create table authors(
name text
);
-- 2.sql
create unique index concurrently
authors_name_key on authors(name);
-- 3.sql
set local lock_timeout = '2s';
alter table authors
add constraint authors_name_pkey
primary key using index authors_name_key;
Safer migration
-- 1.sql
create table authors(
name text
);
-- 2.sql
create unique index concurrently
authors_name_key on authors(name);
-- 3.sql
set local lock_timeout = '2s';
-- eugene: ignore E2
-- This is a demo of W14, so we can ignore E2 instead of the
-- multi-step migration to make the column NOT NULL safely
alter table authors
alter column name set not null;
-- 4.sql
alter table authors
add constraint authors_name_pkey
primary key using index authors_name_key;