Specify primary keys for tables without

Relates to https://gitlab.com/gitlab-org/gitlab/-/issues/251072

changelogs/unreleased/ab-primary-keys.yml

+---
+title: Specify primary key for tables without
+merge_request: 45198
+author:
+type: other

db/migrate/20201014163633_specify_primary_key_where_missing.rb

+# frozen_string_literal: true
+
+class SpecifyPrimaryKeyWhereMissing < ActiveRecord::Migration[6.0]
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+
+  disable_ddl_transaction!
+
+  TABLES = {
+    project_authorizations: [:index_project_authorizations_on_user_id_project_id_access_level, %i(user_id project_id access_level)],
+    analytics_language_trend_repository_languages: [:analytics_repository_languages_unique_index, %i(programming_language_id project_id snapshot_date)],
+    approval_project_rules_protected_branches: [:index_approval_project_rules_protected_branches_unique, %i(approval_project_rule_id protected_branch_id)],
+    ci_build_trace_sections: [:index_ci_build_trace_sections_on_build_id_and_section_name_id, %i(build_id section_name_id)],
+    deployment_merge_requests: [:idx_deployment_merge_requests_unique_index, %i(deployment_id merge_request_id)],
+    issue_assignees: [:index_issue_assignees_on_issue_id_and_user_id, %i(issue_id user_id)],
+    issues_prometheus_alert_events: [:issue_id_prometheus_alert_event_id_index, %i(issue_id prometheus_alert_event_id)],
+    issues_self_managed_prometheus_alert_events: [:issue_id_self_managed_prometheus_alert_event_id_index, %i(issue_id self_managed_prometheus_alert_event_id)],
+    merge_request_diff_commits: [:index_merge_request_diff_commits_on_mr_diff_id_and_order, %i(merge_request_diff_id relative_order)],
+    merge_request_diff_files: [:index_merge_request_diff_files_on_mr_diff_id_and_order, %i(merge_request_diff_id relative_order)],
+    milestone_releases: [:index_miletone_releases_on_milestone_and_release, %i(milestone_id release_id)],
+    project_pages_metadata: [:index_project_pages_metadata_on_project_id, %i(project_id)],
+    push_event_payloads: [:index_push_event_payloads_on_event_id, %i(event_id)],
+    repository_languages: [:index_repository_languages_on_project_and_languages_id, %i(project_id programming_language_id)],
+    user_interacted_projects: [:index_user_interacted_projects_on_project_id_and_user_id, %i(project_id user_id)],
+    users_security_dashboard_projects: [:users_security_dashboard_projects_unique_index, %i(project_id user_id)]
+  }.freeze
+
+  def up
+    TABLES.each do |table, (unique_index, _)|
+      with_lock_retries do
+        execute "ALTER TABLE #{table} ADD CONSTRAINT #{table}_pkey PRIMARY KEY USING INDEX #{unique_index}" if index_exists_by_name?(table, unique_index)
+      end
+    end
+  end
+
+  def down
+    TABLES.each do |table, (unique_index, columns)|
+      add_concurrent_index table, columns, name: unique_index, unique: true
+
+      with_lock_retries do
+        execute "ALTER TABLE #{table} DROP CONSTRAINT #{table}_pkey"
+      end
+    end
+  end
+end

db/schema_migrations/20201014163633

+591bb8d685c686cced324825e7bec01711aee328176c1c5396a9e61847cb6fab
\ No newline at end of file

spec/db/schema_spec.rb

@@ -241,25 +241,9 @@ RSpec.describe 'Database schema' do
   context 'primary keys' do
     let(:exceptions) do
       %i(
-        analytics_language_trend_repository_languages
-        approval_project_rules_protected_branches
-        ci_build_trace_sections
-        deployment_merge_requests
         elasticsearch_indexed_namespaces
         elasticsearch_indexed_projects
-        issue_assignees
-        issues_prometheus_alert_events
-        issues_self_managed_prometheus_alert_events
         merge_request_context_commit_diff_files
-        merge_request_diff_commits
-        merge_request_diff_files
-        milestone_releases
-        project_authorizations
-        project_pages_metadata
-        push_event_payloads
-        repository_languages
-        user_interacted_projects
-        users_security_dashboard_projects
       )
     end