Processing Direct Data Sets

This topic covers the following subtopics.

Topic
Using the Basic Direct Access Method (BDAM)
Processing a Direct Data Set Sequentially
Organizing a Direct Data Set
Creating a Direct Data Set
Referring to a Record
Adding or Updating Records
Sharing DCBs

If you use BDAM, be aware of the following limitations:

Keyed blocks use hardware keys, which are less efficient than VSAM keys.
BDAM does not support extended format data sets.
The use of relative track addressing or actual device addresses easily can lead to program logic that is dependent on characteristics that are unique to certain device types.
Updating R0 can be inefficient.
Load mode does not support 31-bit addressing mode.

VSAM does not have any of these limitations.