iX V6.5 (30391-90011)

Chapter 10 473

Internal Structures and Techniques

Data Set Internal Structures

Figure 10-1. Media Record for Detail Entry

Media Records of Master Data Sets

Media records of master data entries are composed of the following:

• A 10-byte ﬁeld serving as a synonym chain head for primary entries or a synonym chain

link for secondary entries.

• A 3 times n word ﬁeld in which the chain heads of all related detail chains are

maintained. n is the number of paths deﬁned for the master data set. Between 0 and 16

paths can be deﬁned.

• The data entry itself.

Figure 10-2. illustrates the media record for a primary entry of a master data set with two

paths deﬁned.

Figure 10-2. Media Record for Primary Entry

Figure 10-3. illustrates a media record for a secondary entry of a master data set with two

paths deﬁned.