在IndexedDB中将数据从旧版本迁移到新版本

Question

request.onupgradeneeded = e => {
                console.log("onupgradeneeded");
                let db = e.target.result;
                var txn = e.target.transaction;
                if (e.oldVersion < 1) {
                  

db.createObjectStore(DB_Initial_Store_State, {
                keyPath: "id"
              });
            } else {
              let objCreate = db.createObjectStore(DB_New_Store_State, {
                keyPath: "id"
              });
             //How to migrate the data from DB_Initial_Store_State to DB_New_Store_State
            }
          };

谁能解释一下如何将数据从旧版本的索引数据库状态迁移到新状态？