In Entity-Relationship (ER) modeling connection traps are a known problems. But the literature does not seem to have provided an adequate treatment of it. Moreover, it seems to be only a special case of a more fundamental problem of whether a piece of information can be represented by a database that is specified by an ER schema. To develop a systematic treatment for this problem, in this paper we suggest adopting a semiotic approach, which enables the separation of topological connections at the syntactic level and semantic connections, and an examination of the inter-relationships between them. Based on this, we propose and describe the notion of ‘classes of a path’ in an ER schema, and then indicate its implications to ER modeling.