Introduction

Working with databases

Option D of the "Service Manager Selection Menu" enables you to display the databases of the selected subsystem ID.

  • Communication is offered with the help of Beta Query Language (BQL).
  • Beta Systems product databases use internally formatted VSAM ESDS datasets to store data. All descriptions of fields, tables, and keys are stored in the database definition file (DD BnnDEF).
  • The connections between the logical file and the physical dataset names are defined in the database description.
  • A field is defined by its name, its type (character, integer, small integer, byte or flag) and its internal and external length.
  • A table is a collection of fields which are assigned to a logical file name and if necessary to a logical key file name.
  • A table may possess one or more keys to accelerate access to the individual records in the table.

Example: VDF databases

The following databases are described as examples of databases necessary for the VTAM Dialog Facility (VDF):

hlq.DEF

The database definition file contains all the definitions of the files, tables, and records on the database.

hlq.VDF

System parameters and user profiles are stored in this database.

hlq.VDF.KEY

The keys used by the VDF database are stored in this database.

hlq.SYNC

The synchronization file is used to control access to the databases.

Database Selection Menu

Select option D from the "Service Manager Selection Menu" to call the "Database Selection Menu". This is the starting point for working with databases: 

PEB5DAS0 ---------------------------------------------------------------------
 Option ===> __________________________________________________________________

 Database Selection Menu Subsys-ID - F09A
 Sysname - BETA


 1 DATABASE - Display or Update System Database

 2 DICTIONARY - Display Dictionary Information

 3 STATISTICS - Statistics of Database Usage

 Q QUERY - Database Query







 Select one of the above options. Press END to return to the previous menu.