为什么在此代码中从未调用过onupgradeneed? [英] Why is onupgradeneeded never called in this code?

问题描述

我正在尝试在索引数据库中插入数据，但是永远不会调用onupgradeneed函数，而只会调用成功.数据库的版本始终相同(它是一个全局变量). 我知道，为了适应onupgradeneed，版本必须始终相同.就我而言，就是这种方式. 所以，我没有数据...该怎么办? 谢谢！

I'm trying to insert data in my indexed db, but the function onupgradeneed never is called, just onsuccess. The version of the database is always the same (it is a global variable). I have understood that in order to get into onupgradeneed the version have to be always the same. In my case, it is in this way. So, I have no data... What can I do? Thanks!

var db;
var dbname = "mi";
var dbversion = 1;

function abrirDB()
{
    if (plataforma == plataformaW8) {
        if (db == null) {
            var request = window.indexedDB.open(dbname, dbversion);
            request.onsuccess = function (evt) {
                db = evt.target.result;
                if (db.objectStoreNames.length == 0)
                    crearDB();
            };
            }
        }
}
function crearDB() {


   //Declaración datos BBDD

        var paisesData = [{ id_pais: 1, pais: "Arabia Saudí", continente: "Asia", capital: "Riad", paisurl: "arabiasaudi", continenteurl: "asia" },
      { id_pais: 2, pais: "Emiratos Árabes Unidos", continente: "Asia", capital: "Abu Dhabi", paisurl: "emiratosarabes", continenteurl: "asia" }];


    //////////

    //Abrir BBDD
    var request =window.indexedDB.open(dbname, dbversion);

    request.onerror = function (evt) {
        console.log("Error al abrir la bbdd" + evt.target.errorCode);
    };


    request.onupgradeneeded = function (evt) {
       db = evt.target.result;

        var storePaises = db.createObjectStore(storePaisesNombre, { keyPath: "id_pais", autoincrement: false, unique: true });
      .......
    request.onsuccess = function (evt) {
        //db = request.result;
        db = evt.target.result;
    };

  }

推荐答案

将dbversion变量更改为2.这样，数据库将以较新的版本打开，并且onupgradeneeded回调将被调用

Change your dbversion variable to 2. This way the db will open in a newer version and the onupgradeneeded callback will get called

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