VSAM Volume Record (VVR)
VSAM volume records contain information about the VSAM data sets residing on the volume with the VVDS. If more than one VVR is associated with a component, the first (primary) VVR contains information pertaining to the data set as a whole. The other (secondary) VVRs do not repeat the primary information in their records but contain information for their own component, such as extents, RBAs, and allocation quantities, and most of the information needed to open a VSAM data set.
Data Set Type | Number of Primary VVRs |
---|---|
Entry-sequenced data set | 1 per volume for the data component |
Key-sequenced data set with the NOIMBED option | 1 per volume for the data component; 1 for the index |
Key-sequenced data set with the IMBED option | 1 per volume for the data component; 1 for the index; 1 per volume for the sequence set |
Key range key-sequenced data set with the NOIMBED option | 1 per key range per volume; 1 for the index |
Key range key-sequenced data set with the IMBED option | 2 per key range per volume; 1 per volume for the index |
- VVR header cell
- VVR data set information cell
- VVR AMDSB cell
- VVR volume information cell
The VVRLEN field of the VVR header cell contains the length of
the entire VVR. The VVRTYPE field of the same cell contains the VVR
type code, which is either Z
(for primary) or Q
(for
secondary).
![](da6c1006.gif)
Figure 2 shows examples of the information contained in each type of VVR cell.
![](da6c1007.gif)