ORMLite uniqueCombo with null-value

Question

Can a uniqueCombo identify a field when one or more fields of this combo are null?

class Entity {
    @DatabaseField(columnName = "fieldA", canBeNull = true, uniqueCombo = true)
    private String fieldA;

    @DatabaseField(columnName = "fieldB", canBeNull = true, uniqueCombo = true)
    private String fieldB;
}

If there was a record in table Entity where fieldA is 'John'and fieldB is null, would querying this result in 1 record?

dao.queryForFirst(
    dao.queryBuilder().
        where().
            eq("fieldA", "John").
        and().
            eq("fieldB", null).
        prepare());

Answer 1

Ok, this seems to be tied to the DB engine. When using MySQL, it is handeled by the rules the selected MySQL engine dicates.

This answer was very helpful