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The CA IDMS/DB Environment

Set is the Basic Structure

In CA IDMS/DB, the basic structure is the set. A set consists of record types that are related as owner and member. Individual record types can participate in more than one relationship (set) either as owner or member (that is, a member record type can have more than one owner record type).

Multiple Ownership Support

Support for multiple ownership is the most basic difference between DL/I and CA IDMS/DB. In DL/I, a child segment (equivalent to a member record type) can have one and only one parent segment (equivalent to an owner record type).

Note: DL/I's support for bidirectional logical relationships provides the functional equivalent of multiple ownership.