Android的升级SQLite数据库问题 [英] Android upgrade sqlite database issue

问题描述

我有我的升级SQLite数据库有点问题。现在我用这样的：

I have a little issue with upgrading my sqlite database. For now I'm using this :

@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
    Log.w("","UPGRADE DATABASE : "+" oldVErsion : "+oldVersion+" newVersion : "+newVersion);
    switch(newVersion){
    case 2:
        Log.w("","UPGRADE DATABASE : "+newVersion);
        db.execSQL("ALTER TABLE collection_lang ADD COLUMN bonus_text VARCHAR(200)");
        db.execSQL("ALTER TABLE collection_lang ADD COLUMN quantity integer");
    case 3:
        Log.w("","UPGRADE DATABASE : "+newVersion);
        db.execSQL("ALTER TABLE users ADD COLUMN firstName varchar(70)");
        db.execSQL("ALTER TABLE users ADD COLUMN lastName varchar(70)");
        db.execSQL("ALTER TABLE users ADD COLUMN user varchar(70)");
    }
}

它的工作，如果你已经从beggining..but安装的应用程序，如果你现在安装它，它只会在情况下3 ，因为目前的版本上运行的查询3。

It's working if you already have the application installed from the beggining..but if you install it now, it will run queries only in case 3, because the current version is 3.

我需要找到一种方式来运行从一开始查询..如果我的数据库的最后一个版本是5，我想先运行的情况下2比3的情况下，比4，最后的情况下5.所以我不需要写从一开始的查询，因为它会崩溃的老用户。

I need to find a way to run the queries from the beginning.. if my last version of database is 5, I want to run first the case 2, than case 3, than 4 and at last case 5. So I won't need to write all the queries from the beginning because it will crash for the old users.

任何想法如何实现这一目标？

Any ideas how to achieve this?

推荐答案

距离的情况下2添加到查询的情况下3和每个案件之后添加break语句。所以你的情况就会是这样的：

Just add your queries from the case 2 into the case 3 and add break statement after each case. So in your case it will be something like this:

@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
    Log.w("","UPGRADE DATABASE : "+" oldVErsion : "+oldVersion+" newVersion : "+newVersion);
    switch(newVersion){
    case 2:
        Log.w("","UPGRADE DATABASE : "+newVersion);
        db.execSQL("ALTER TABLE collection_lang ADD COLUMN bonus_text VARCHAR(200)");
        db.execSQL("ALTER TABLE collection_lang ADD COLUMN quantity integer");
        break;
    case 3:
        Log.w("","UPGRADE DATABASE : "+newVersion);
        db.execSQL("ALTER TABLE collection_lang ADD COLUMN bonus_text VARCHAR(200)");
        db.execSQL("ALTER TABLE collection_lang ADD COLUMN quantity integer");
        db.execSQL("ALTER TABLE users ADD COLUMN firstName varchar(70)");
        db.execSQL("ALTER TABLE users ADD COLUMN lastName varchar(70)");
        db.execSQL("ALTER TABLE users ADD COLUMN user varchar(70)");
        break;
    }
}

更新：不要smthg是这样的：

Update: Do smthg like this:

switch(newVersion){
case 2:
    Log.w("","UPGRADE DATABASE : "+newVersion);
    db.execSQL("ALTER TABLE collection_lang ADD COLUMN bonus_text VARCHAR(200)");
    db.execSQL("ALTER TABLE collection_lang ADD COLUMN quantity integer");
    break;
case 3:
    Log.w("","UPGRADE DATABASE : "+newVersion);
    switch(oldVersion) {
        case 1:
            db.execSQL("ALTER TABLE collection_lang ADD COLUMN bonus_text VARCHAR(200)");
            db.execSQL("ALTER TABLE collection_lang ADD COLUMN quantity integer");
            db.execSQL("ALTER TABLE users ADD COLUMN firstName varchar(70)");
            db.execSQL("ALTER TABLE users ADD COLUMN lastName varchar(70)");
            db.execSQL("ALTER TABLE users ADD COLUMN user varchar(70)");
            break;
        case 2: 
            db.execSQL("ALTER TABLE users ADD COLUMN firstName varchar(70)");
            db.execSQL("ALTER TABLE users ADD COLUMN lastName varchar(70)");
            db.execSQL("ALTER TABLE users ADD COLUMN user varchar(70)");
            break;
    }

}

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