type OperationResult<Op> = Op extends "create" ? {
  id: string;
 } : Op extends "update" ? 
  | {
  id: string;
 }
  | null : Op extends "delete" ? 
  | {
  id: string;
 }
  | null : Op extends "findUnique" ? 
  | {
  id: string;
 }
  | null : Op extends "findMany" ? {
  id: string;
 }[] : Op extends "findFirst" ? 
  | {
  id: string;
 }
  | null : Op extends "count" ? number : Op extends "createMany" ? {
  count: number;
  records: {
     id: ...;
    }[];
 } : Op extends "updateMany" ? {
  count: number;
 } : Op extends "deleteMany" ? {
  count: ...;
 } : ... extends ... ? ... : ...;