Please wrap migrate() in a transaction and throws a SQLException

[yukoba]

Could you please wrap migrate() in a transaction and throws a SQLException?
The current code destroys the database when a SQLException is thrown.

[Bertkiing]

I meet the same problem...

[yukoba]

What I want is this.
yukoba@431d00e

[Bertkiing]

I think it can help you. Good luck!!!

http://stackoverflow.com/questions/16154113/greendao-schema-upgrade

[xuzc]

thanks ☺ @yukoba

[zzzhouzhong]

@yukoba i find that OpenHelper.onUpgrade() will be execute in transaction by default.

@Override
public void onUpgrade(Database db, int oldVersion, int newVersion) {
    boolean isInTransaction = db.inTransaction();//Here isInTransaction=true
}

My Conclusion is:
1.There is no need to begin a transaction
2.Throw all exception and catch it in onUpgrade()(Don't catch SQLException in MigrationHelper).

//MigrationHelper.java
....
public static void migrate(Database database, Class>... daoClasses) throws NoSuchMethodException, IllegalAccessException, InvocationTargetException {
....
}
....

//MyOpenHelper.java
......
@OverRide
public void onUpgrade(Database db, int oldVersion, int newVersion) {
Log.i(TAG, "Upgrading schema from version " + oldVersion + " to " + newVersion);
try {
MigrationHelper.migrate(db,XXDAO.class);
Log.i(TAG, "Upgrading success!!!");
} catch (Exception e) {
e.printStackTrace();
Log.e(TAG, "Upgrading failed, drop all tables!!!");
DaoMaster.dropAllTables(db, true);
onCreate(db);
}
}
....