CA Culprit in the CA IDMS/DB Environment › PATH Parameter › Accessing Database Records › Defining a Path

Defining a Path

A set relationship must exist between the records specified on the path, unless the PATH parameter specifies a dummy path; dummy paths are discussed later in this chapter. The sets can be implemented with embedded pointers or with an index. The following rules apply to the sequence of records that define the path:

• The relationship between the entry record and the next record on the path can be either owner-to-member or member-to-owner, as shown in the example below:

  Correct Paths:     EMPLOYEE EMPOSITION
                     EMPLOYEE DEPARTMENT
  
  Incorrect Path:    EMPLOYEE JOB
  

• The record that follows an owner-to-member traversal must be related to the member record, as shown below:

  Correct Path:    EMPLOYEE EMPOSITION JOB
  
  Incorrect Path:  EMPLOYEE EMPOSITION EXPERTISE
  

• The record that follows a member-to-owner traversal can be related to the owner record or to any previous record named on the path, provided the previous record and any intervening records were retrieved using a member-to-owner traversal, as shown below:

  Correct Paths:   COVERAGE EMPLOYEE OFFICE EXPERTISE
                   EXPERTISE EMPLOYEE OFFICE SKILL
                   EXPERTISE EMPLOYEE DEPARTMENT COVERAGE
  
  Incorrect Path:  EXPERTISE EMPLOYEE EMPOSITION SKILL
  

• A single record type can occur more than once on a path, as shown below:

  Correct Paths:  EMPLOYEE STRUCTURE (REPORTS-TO) EMPLOYEE (MANAGES)
                  EMPLOYEE COVERAGE EMPLOYEE EXPERTISE