How can I avoid concurrency problems when using SQLite on Android?

What would be considered the best practices when executing queries on an SQLite database within an Android app? Is it safe to run inserts, deletes and select queries from an AsyncTask's doInBackground? Or should I use the UI Thread? I suppose that database queries can be "heavy" and should not use the UI thread as it can lock up the app - resulting in an Application Not Responding (ANR). If I have

[webarata3]

すごいの引っかかった。

[shimooka]

『So, multiple threads? Use one helper. Period.』

[teppeis]

ormlite