Cleanup first_mentioned_in_commit_at migration

db/post_migrate/20211207090503_cleanup_first_mentioned_in_commit_jobs.rb

+# frozen_string_literal: true
+
+class CleanupFirstMentionedInCommitJobs < Gitlab::Database::Migration[1.0]
+  disable_ddl_transaction!
+
+  MIGRATION = 'FixFirstMentionedInCommitAt'
+  INDEX_NAME = 'index_issue_metrics_first_mentioned_in_commit'
+
+  def up
+    finalize_background_migration(MIGRATION)
+
+    remove_concurrent_index_by_name :issue_metrics, name: INDEX_NAME
+  end
+
+  def down
+    # Handles reported schema inconsistencies (column with or without timezone)
+    # We did the same in db/post_migrate/20211004110500_add_temporary_index_to_issue_metrics.rb
+    condition = Gitlab::BackgroundMigration::FixFirstMentionedInCommitAt::TmpIssueMetrics
+      .first_mentioned_in_commit_at_condition
+    add_concurrent_index :issue_metrics, :issue_id, where: condition, name: INDEX_NAME
+  end
+end

db/schema_migrations/20211207090503

+c30656c3f079e789f386b5b607710a7d4df6d2eb20bd457bab3a2e8d9eeb051b
\ No newline at end of file

db/structure.sql

@@ -26346,8 +26346,6 @@ CREATE UNIQUE INDEX index_issue_links_on_source_id_and_target_id ON issue_links
 
 CREATE INDEX index_issue_links_on_target_id ON issue_links USING btree (target_id);
 
-CREATE INDEX index_issue_metrics_first_mentioned_in_commit ON issue_metrics USING btree (issue_id) WHERE (date_part('year'::text, first_mentioned_in_commit_at) > (2019)::double precision);
-
 CREATE INDEX index_issue_metrics_on_issue_id_and_timestamps ON issue_metrics USING btree (issue_id, first_mentioned_in_commit_at, first_associated_with_milestone_at, first_added_to_board_at);
 
 CREATE INDEX index_issue_on_project_id_state_id_and_blocking_issues_count ON issues USING btree (project_id, state_id, blocking_issues_count);