Question

I need to create a SQLite DB for my application. I’ll need to store text in several European languages, so there will be plenty of accented characters and other weird marks. I’m extending SQLiteOpenHelper.

Inspecting the .db file I noticed there’s an extra table named android_metadata. There’s a single column named locale, which is set to “en_US” by default in my simulator.

I’ve readed the SQLite section in the developer guide, and also the javadocs for SQLiteOpenHelper and SQLiteDatabase, searched in SO and in Google, but nowhere I could find what is the correct place to set the locale to the DB, or if it is really neccesary. Guessing it should be done at DB creation, I tried calling db.setLocale in the helper’s onCreate method, but I’m, getting this exception:

BEGIN TRANSACTION failed setting locale
FATAL EXCEPTION: Thread-9
android.database.sqlite.SQLiteException: cannot start a transaction within a transaction
at android.database.sqlite.SQLiteDatabase.native_setLocale(Native Method)
at android.database.sqlite.SQLiteDatabase.setLocale(SQLiteDatabase.java:1950)

This is how my method looks:

public class MyOpenHelper extends SQLiteOpenHelper {

    @Override
    public void onCreate(SQLiteDatabase db) {   
        db.setLocale(new Locale("en","EN"));
        ...
    }

    ...
}

And here are my questions:

1. Do I really need to set the locale to the DB? I don’t really need to get the queries sorted out of the box, as I can always sort the results myself later.
2. Where should I call setLocale?

Answer 1

1. You’ll need to set the locale only if you intend to use the LOCALIZED collation algorithm, which depends on the system locale,
2. As mentioned in your answer, call setLocale() on onConfigure().