Question

I call SQLiteDatabase.query and get a Cursor. While I’m still iterating over that cursor, is it safe to issue other queries from the same thread?

Answer 1

Yes. You can, from within the same thread, have multiple outstanding queries and independently access each of the cursors.

I added the following code to a test activity and it runs as expected:

SQLiteDatabase connection = getApplicationContext().openOrCreateDatabase("foo.db", MODE_PRIVATE, null);
try {
    connection.execSQL("drop table if exists person");
    connection.execSQL("create table person (id integer, name string)");
    ContentValues cv = new ContentValues();
    cv.put("id", 1);
    cv.put("name", "leo");
    connection.insert("person", null, cv);
    cv = new ContentValues();
    cv.put("id", 2);
    cv.put("name", "yui");
    connection.insert("person", null, cv);

    Cursor rs = connection.query("person", new String[] {"id", "name" }, null, null, null, null, null);

    while(rs.moveToNext())
    {
        System.out.println("name = " + rs.getString(1));
        System.out.println("id = " + rs.getString(0));

        Cursor rs2 = connection.query("person", new String[] {"id", "name" }, null, null, null, null, null);
        while (rs2.moveToNext()) {
            System.out.println("name = " + rs2.getString(1));
            System.out.println("id = " + rs2.getString(0));
        }
    }
} catch (Exception e) {
    System.out.println("Exception " + e);
}