Finalize ci_job_artifacts conversion to bigint

- Migrate all foreign keys to new column
- Migrate indexes to use new columns
- Rename columns to their original names
- Regenerate trigger for new columns

Relates to https://gitlab.com/gitlab-org/gitlab/issues/325615

Changelog: other

db/post_migrate/20210706212710_finalize_ci_job_artifacts_bigint_conversion.rb

+# frozen_string_literal: true
+
+# See https://docs.gitlab.com/ee/development/migration_style_guide.html
+# for more information on how to write migrations for GitLab.
+
+class FinalizeCiJobArtifactsBigintConversion < ActiveRecord::Migration[6.1]
+  include Gitlab::Database::MigrationHelpers
+
+  disable_ddl_transaction!
+
+  TABLE_NAME = 'ci_job_artifacts'
+
+  def up
+    ensure_batched_background_migration_is_finished(
+      job_class_name: 'CopyColumnUsingBackgroundMigrationJob',
+      table_name: TABLE_NAME,
+      column_name: 'id',
+      job_arguments: [%w[id job_id], %w[id_convert_to_bigint job_id_convert_to_bigint]]
+    )
+
+    swap
+  end
+
+  def down
+    swap
+  end
+
+  private
+
+  def swap
+    add_concurrent_index TABLE_NAME, :id_convert_to_bigint, unique: true, name: 'index_ci_job_artifact_on_id_convert_to_bigint'
+    # This is to replace the existing "index_ci_job_artifacts_for_terraform_reports" btree (project_id, id) where (file_type = 18)
+    add_concurrent_index TABLE_NAME, [:project_id, :id_convert_to_bigint], name: 'index_ci_job_artifacts_for_terraform_reports_bigint', where: "file_type = 18"
+    # This is to replace the existing "index_ci_job_artifacts_id_for_terraform_reports" btree (id) where (file_type = 18)
+    add_concurrent_index TABLE_NAME, [:id_convert_to_bigint], name: 'index_ci_job_artifacts_id_for_terraform_reports_bigint', where: "file_type = 18"
+
+    # Add a FK on `project_pages_metadata(artifacts_archive_id)` to `id_convert_to_bigint`, the old FK (fk_69366a119e)
+    # will be removed when ci_job_artifacts_pkey constraint is droppped.
+    fk_artifacts_archive_id = concurrent_foreign_key_name(:project_pages_metadata, :artifacts_archive_id)
+    fk_artifacts_archive_id_tmp = "#{fk_artifacts_archive_id}_tmp"
+    add_concurrent_foreign_key :project_pages_metadata, TABLE_NAME,
+      column: :artifacts_archive_id, target_column: :id_convert_to_bigint,
+      name: fk_artifacts_archive_id_tmp,
+      on_delete: :nullify,
+      reverse_lock_order: true
+
+    with_lock_retries(raise_on_exhaustion: true) do
+      # We'll need  ACCESS EXCLUSIVE lock on the related tables,
+      # lets make sure it can be acquired from the start
+      execute "LOCK TABLE #{TABLE_NAME}, project_pages_metadata IN ACCESS EXCLUSIVE MODE"
+
+      # Swap column names
+      temp_name = 'id_tmp'
+      execute "ALTER TABLE #{quote_table_name(TABLE_NAME)} RENAME COLUMN #{quote_column_name(:id)} TO #{quote_column_name(temp_name)}"
+      execute "ALTER TABLE #{quote_table_name(TABLE_NAME)} RENAME COLUMN #{quote_column_name(:id_convert_to_bigint)} TO #{quote_column_name(:id)}"
+      execute "ALTER TABLE #{quote_table_name(TABLE_NAME)} RENAME COLUMN #{quote_column_name(temp_name)} TO #{quote_column_name(:id_convert_to_bigint)}"
+
+      # We need to update the trigger function in order to make PostgreSQL to
+      # regenerate the execution plan for it. This is to avoid type mismatch errors like
+      # "type of parameter 15 (bigint) does not match that when preparing the plan (integer)"
+      function_name = Gitlab::Database::UnidirectionalCopyTrigger.on_table(TABLE_NAME).name([:id, :job_id], [:id_convert_to_bigint, :job_id_convert_to_bigint])
+      execute "ALTER FUNCTION #{quote_table_name(function_name)} RESET ALL"
+
+      # Swap defaults
+      execute "ALTER SEQUENCE ci_job_artifacts_id_seq OWNED BY #{TABLE_NAME}.id"
+      change_column_default TABLE_NAME, :id, -> { "nextval('ci_job_artifacts_id_seq'::regclass)" }
+      change_column_default TABLE_NAME, :id_convert_to_bigint, 0
+
+      # Swap PK constraint
+      execute "ALTER TABLE #{TABLE_NAME} DROP CONSTRAINT ci_job_artifacts_pkey CASCADE" # this will drop ci_job_artifacts_pkey primary key
+      rename_index TABLE_NAME, 'index_ci_job_artifact_on_id_convert_to_bigint', 'ci_job_artifacts_pkey'
+      execute "ALTER TABLE #{TABLE_NAME} ADD CONSTRAINT ci_job_artifacts_pkey PRIMARY KEY USING INDEX ci_job_artifacts_pkey"
+
+      # Rename the rest of the indexes (we already hold an exclusive lock, so no need to use DROP INDEX CONCURRENTLY here
+      execute 'DROP INDEX index_ci_job_artifacts_for_terraform_reports'
+      rename_index TABLE_NAME, 'index_ci_job_artifacts_for_terraform_reports_bigint', 'index_ci_job_artifacts_for_terraform_reports'
+      execute 'DROP INDEX index_ci_job_artifacts_id_for_terraform_reports'
+      rename_index TABLE_NAME, 'index_ci_job_artifacts_id_for_terraform_reports_bigint', 'index_ci_job_artifacts_id_for_terraform_reports'
+
+      # Change the name of the temporary FK for project_pages_metadata(artifacts_archive_id) -> id
+      rename_constraint(:project_pages_metadata, fk_artifacts_archive_id_tmp, fk_artifacts_archive_id)
+    end
+  end
+end

db/schema_migrations/20210706212710

+33162af4ef99c32d3c5b38479e407d4911a8d3dce53407dbee6e5745c8e945ae
\ No newline at end of file

db/structure.sql

@@ -10785,7 +10785,7 @@ CREATE SEQUENCE ci_instance_variables_id_seq
 ALTER SEQUENCE ci_instance_variables_id_seq OWNED BY ci_instance_variables.id;
 
 CREATE TABLE ci_job_artifacts (
-    id integer NOT NULL,
+    id_convert_to_bigint integer DEFAULT 0 NOT NULL,
     project_id integer NOT NULL,
     job_id_convert_to_bigint integer DEFAULT 0 NOT NULL,
     file_type integer NOT NULL,
@@ -10798,7 +10798,7 @@ CREATE TABLE ci_job_artifacts (
     file_sha256 bytea,
     file_format smallint,
     file_location smallint,
-    id_convert_to_bigint bigint DEFAULT 0 NOT NULL,
+    id bigint NOT NULL,
     job_id bigint NOT NULL,
     CONSTRAINT check_27f0f6dbab CHECK ((file_store IS NOT NULL))
 );