From https://gitlab.com/gitlab-com/infrastructure/issues/1709 (private to GitLab employees): * Wrong data type: created_at should be timestamptz * Wrong data type: updated_at should be timestamptz * Missing constraint: created_at NOT NULL * Missing constraint: updated_at NOT NULL * Missing constraint: project_id NOT NULL * Missing FK: runner_id -> runners (2 entries violate this rule) * Missing FK: project_id -> projects (178 entries violate this rule)