The IBM Informix database servers allows you to query more than one database of the same database server or across multiple database servers. This type of query is called a distributed query. The database servers can reside on a single host computer, on different computers of the same network, or on a gateway. (In general, most features and restrictions that this chapter describes for distributed queries also apply to function calls and to distributed INSERT, DELETE, or UPDATE operations that reference objects or data in more than one database.)