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Frequently asked questions

What is tcVISION?

tcVISION is a powerful change data capture (CDC) platform for users of IBM mainframes. tcVISION automatically identifies the changes applied to mainframe databases and files. No programming effort is necessary to obtain the changed data. tcVISION continuously propagates the changed data to the target systems in real time or can perform the process in time intervals. tcVISION offers a rich set of processing and controlling mechanisms to guarantee a data exchange implementation that is fully auditable. tcVISION contains powerful bulk processors that perform the initial load of mass data or the cyclic exchange of larger data volumes in an efficient, fast and reliable way.

Why has tcVISION been developed?

The growing number of distributed application systems that maintain their individual databases as well as the mobility of applications demand an ongoing exchange of data between mainframe and Open System server. In a market with no borders and no time limits the end-user demands highly accurate and timely accurate information. Innovative solutions for an ongoing information exchange between the individual application systems are required to implement the "Real-time Enterprise".

Why should a corporation use tcVISION?

The number of applications that operate a database is increasing and the demand to constantly synchronize data between the mainframe and Open System platforms becomes a critical operational issue. The traditional methods for the exchange of mass data faces limits (limited batch windows) and the general cost pressure requires efficient solutions for data exchange, data synchronization and data replication.

What methods are being provided to capture the changed data?

tcVISION supports different "Capture" methods. These methods can be individually used as application and data processing flow requires it. Real-time/Near Real-time DBMS Extensions The changed data will be determined using database exits. These are the standard exits provided by the DBMS. Log Processing The changed data is being selected and processed from the active and archived log files of the datasource. Compare Processing Data changes are being determined by comparing a "Snapshot file" and the current original file. At the same time a new snapshotfile can be created that will be used for the next compare.

What file data structures on the IBM mainframe systems are supported to capture the changed data?

tcVISION captures changed data for the following data organizations: DB2 Real-time/Near Real-time, Log Processing, Compare Processing IMS Real-time/Near Real-time, Log Processing, Compare Processing ADABAS Real-time/Near Real-time, Log Processing, Compare Processing CA-IDMS Real-time/Near Real-time, Log Processing, Compare Processing VSAM/CICS Real-time/Near Real-time, Log Processing, Compare Processing VSAM - Compare Processing Sequential - Compare Processing CA-Datacom - Log Processing, Compare Processing

Are Logical Units of Work (LUW) supported?

Yes, tcVISION offers a LUW Manager for capturing methods "Real-time/Near Real-time" and "Log Processing". You can use this manager to make sure that all transaction changes are being applied in the correct sequence to the target system.

What systems can I use as a target for my changed data?

The changed data can be applied to any target system. These systems can either reside on IBM Mainframes, UNIX/LINUX/Linux on System z or WINDOWS platforms. tcVISION offers a variety of options how the changed data can be propagated to the target system (ODBC, DRDA, ORACLE-OCI, XML, FILE, DB2 etc.).

Is it possible to maintain the changed data and process it before they are implemented into the target system?

Yes, the changed data can be processed and maintained. To do this tcVISION offers certain processing point (stages). At any of thes stages the changed data is available in a processing specific format. This guarantees a high degree of flexibility and assures that all processing requirements of your organisation can be handled.

Ara any modification to the operating system required during the installation or is it necessary to IPL the system?

No. No modifications to the operating system (MVS, OS/390, z/OS, VSE) are required. The installation of the mainframe component is simple and straight forward. The distribution libraries must be loaded and a VSAM file must be allocated. The implementation of the DBMS Extensions follows standard and well documented procedures. No IPL is required.

How does tcVISION determine what resources should be controlled to capure the changed data?

A graphical WINDOWS application, the tcVISION Control Board, is used to create so-called "collector definitions". These definitions specifiy the resources that should be supervised to capture changed data.

How do I tell tcVISION how the changed data looks like and what information in this data is of relevance for the propagation process?

tcVISION offers graphical import functions to import copybooks for various programming languages (COBOL, Assembler, PL/I, etc.). During the import of meta data for an IMS or DL/I database the database definitions will be included in the analysis (PSB, DBD). In the case of ADABAS and CA-Datacom the meta data will be automatically extracted from the corresponding dictionary. Meta data for CA-IDMS, including all navigation and connection parameter are automatically extracted from SCHEMA definitions. tcVISION analyses the input data and checks for "Virtual Tables" (OCCURS, OCCURS DEPNDING ON, ADABAS Periodic Groups and Multiple Fields) and offers different processing options during the import.

Can I use tcVISION to perform an initial load of a new database?

Yes, tcVISION offer an intelligent BULK load component. This component can be used to unload data from a mainframe data-source and to drectly load it into a target database.

Does tcVISION contain tools to design and create new databases based upon the structures of the existing data-structures?

Yes, you can use the meta structure definitions that have been created from the mainframe copybooks to automatically create the SQL DML statements for the creation or the Loading of the new target database.

The changed data and the data that should be bulk-loaded must be converted and normalized for the target system. Does that cause a severe performance impact on the mainframe?

With tcVISION practically any computer participating in the propagation process of the changed data can be used to perform the conversion and normalization, hence providing a workload balancing solution. As an example, the captured data can be directly transferred in a highly compressed format to a UNIX machine that has enough free capacity to process the changed data and pass it through the various stages up to the creation of the change SQL-DML. This technique provides the most optimal utilization of available computer resources.