如果需要迁移，领域不会自动删除数据库 [英] Realm not auto-deleting database if migration needed

问题描述

我们正在开发中，数据库模式更改经常发生.由于我们还没有生活，所以不需要迁移.为此，我对Realm进行了如下配置:

We are in development and db schema changes occur often. Since we are not live, migrations are not needed. I therefor configured Realm as follows:

RealmConfiguration config = new RealmConfiguration.Builder(context)
                .name("jt.realm")
                .schemaVersion(1)
                .deleteRealmIfMigrationNeeded() // todo remove for production
                .build();
        Realm.setDefaultConfiguration(config);

但是，更改架构时会引发异常:RealmMigration must be provided

However, when the schema is changed, an exception is thrown: RealmMigration must be provided

我从文档中了解到，由于deleteRealmIfMigrationNeeded()存在于配置中，因此Realm应该自动删除数据库，但这似乎没有发生.为什么会这样?

My understanding from the docs are that the Realm should auto-delete the db since deleteRealmIfMigrationNeeded() is present in the config, but this does not seem to be happening. Why is this occurring?

Android Studio依赖项

编译'io.realm:realm-android:0.86.1'

compile 'io.realm:realm-android:0.86.1'

推荐答案

我们遇到了类似的问题.我们通过添加

We had a similar issue. We solved this by adding

Realm.getInstance(config)

紧接着

Realm.setDefaultConfiguration(config);

我们认为该配置将在首次调用Realm之后进行设置.这次我们不使用任何Realm对象，因此也不例外.

We think the configuration will be set up after Realm is called the first time. This time we don't use any Realm object so there's no exception.

这篇关于如果需要迁移，领域不会自动删除数据库的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！