The following terms are used throughout this guide:

Alias name

An alternate name for a VTS-TSR that can be created, assigned, and used in lieu of the name assigned at VTS-TSR definition. This is a VTS Manager feature. See below for VTS Manager and VTS-TSR definition.

Alternate Index

An Alternate Index is an Index that may be defined for a Data Table. The Alternate Index has an Alternate Index definition (ALT-DEFINITION) that defines the key, organization, and search order. Alternate Indexes are optional, and there is no limit to the number of Alternate Indexes a Data Table may have.

Alternate Index View

A tablesONLINE Alternate Index View is identical to a View but applies to a Data Table when access is through an Alternate Index.

Data Table

A Data Table is the actual raw data. Each Data Table has a table definition (DT-BLOCK) that is used to generate the Index for the Data Table.

DB2 SPAS, WLM-managed DB2 SPAS

DB2 Stored Procedure Address Space managed by WLM.

Delivered defaults

The defaults that are delivered with the product. Also known as factory defaults.


An Index is defined for each Data Table. A Data Table Index is generated dynamically when a table is opened or defined based on the information in the table definition (DT-BLOCK).

Installation defaults

The defaults set at installation time by an administrator, which may or may not be the same as the delivered defaults. Defined using the TBOPTGEN file. (These defaults may be overridden by an individual application using the TBOPT file.)


Linear DataSet used for VTS Manager.

Linked Table

A linked table (also known as a remote table) is created when a user issues a command to open a table that is already open in a VTS-TSR specified in the LIB-LIST. The table entry in the local TSR is linked to the existing open table in the VTS-TSR. No updates are allowed to a linked table.

Multitasking Batch

An MVS region that implements multitasking by attaching multiple Task Control Blocks (TCBs). This can include a batch job that attaches several subtasks or a transaction processing region like DB2 stored procedures that implements multitasking through multiple TCBs.

SAF interface

System Authorization Facility interface that controls resource access. Tools like ACF2, RACF, and Top Secret fall into this category.

Table Expansion

Dynamic allocation of space for tables in the TSR when the current space allocated becomes insufficient.

Temporary Table

A temporary table exists only within a TSR, and is created by the DT command (or IA). It is never stored in a library. A temporary table can be distinguished from a library table using the GD command output—if found, a temporary table will show no dataset name.

TSR, Local TSR

Table Space Region. A data space of up to 2G is used by tableBASE to house tables. The data space is owned by an application in the associated address space. The application uses tableBASE to access data within the tables.

TSR of record

If there is no VTS name in the TB-SUBSYSTEM field of the TB-PARM when a command is being executed, the TSR of record is the local TSR, otherwise it is the VTS-TSR that has its name in the TB-PARM.


A tablesONLINE View provides the field, edit and display attributes for a Data Table with its Index. Previous to Version 5, the View was referred to as a Field Definition Table (FDT).

VTS, DataKinetics VTS

Virtual Table Share. The term “VTS” refers to the DataKinetics VTS product, which permits TSRs to be shared among applications. These shared TSRs are called VTS-TSRs.


A Virtual Table Share (VTS) Table Space Region (TSR) is a shared TSR, and resides in a shared data space. Applications can access tables within a VTS-TSR, and use the information as if it were within their local TSRs.

VTS Agent

The DK1VAGNT program, which initializes VTS-TSRs in tableBASE, and then sits idle until the VTS-TSR is to be terminated.

VTS Gate

The product that provides enhanced security for the shared VTS-TSR capability.

VTS Manager

A DataKinetics Ltd. product that extends the functionality of the VTS shared TSR capabilities.

VTS switch

The action of switching an alias name from one VTS-TSR to another. This is a feature of VTS Manager.