Function mentat_transaction::query::lookup_value_for_attribute

pub fn lookup_value_for_attribute<'sqlite, 'attribute, E>(
    sqlite: &'sqlite Connection, 
    known: Known, 
    entity: E, 
    attribute: &'attribute Keyword
) -> Result<Option<TypedValue>> where
    E: Into<Entid>, 

Return a single value for the provided entity and attribute. If the attribute is multi-valued, an arbitrary value is returned. If no value is present for that entity, None is returned. If attribute doesn't name an attribute, an error is returned.