Function mentat_transaction::query::lookup_value

pub fn lookup_value<'sqlite, 'schema, 'cache, E, A>(
    sqlite: &'sqlite Connection, 
    known: Known, 
    entity: E, 
    attribute: A
) -> Result<Option<TypedValue>> where
    E: Into<Entid>,
    A: 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 isn't an attribute, None is returned.