This chapter describes various ways the client applications can communicate with Teradata Database.
Attachment Methods
Client applications can connect to Teradata Database using one of the following methods: • Network-attached through a Local Area Network (LAN)
• Channel-attached through an IBM mainframe
Network Attachment Methods
Network-attached methods include: • .NET Data Provider for Teradata • Java Database Connectivity (JDBC) • OLE DB Provider for Teradata • Open Database Connectivity (ODBC) • Teradata CLIv2 for NAS
The following figure illustrates the transparent connection between client applications and Teradata Database. Teradata Database Server REQUESTS Client Application Program Client Application Program Client Application Program Client Application Program Client Application Program .NET Data Provider
Network Attachment Methods
.NET Data Provider
.NET Data Provider for Teradata uses CLIv2 to connect, execute commands, and retrieve results from Teradata Database. Results can be processed directly or cached in an ADO.NET DataSet. An ADO.NET DataSet can generate XML, and bridges relational and XML data sources.
Java Database Connectivity
JDBC is a specification for an API. The API allows platform-independent Java applications to access Teradata Database using SQL and, for Teradata Database running on 64-bit Windows and Linux, external stored procedures.
The JDBC API provides a standard set of interfaces for: • Opening connections to databases
• Executing SQL statements • Processing results
Teradata JDBC Driver provides access to Teradata Database using the Java language. Teradata JDBC Driver is a type 4 (pure Java) JDBC Driver. It is a set of Java classes that use TCP/IP to communicate directly with Teradata Database.
OLE DB Provider for Teradata
OLE DB Provider for Teradata allows programmers to design application programs that allow access between Teradata Database and data stores that do no use SQL. The application program (the consumer) requests database information from an intermediate program (the provider), which accesses Teradata Database. The intermediate program receives the response from Teradata Database and returns a copy of the desired data to the application program. OLE DB Provider for Teradata also uses service providers. A service provider enhances the functionality of a provider; for example, the Microsoft Cursor Service for OLE DB adds client-side cursor support to any provider.
Open Database Connectivity
ODBC Driver for Teradata provides an interface to Teradata Databases using the industry standard ODBC API. ODBC Driver for Teradata provides Core-level SQL and Extension-level 1 (with some Extension-level 2) function call capability using the Windows Sockets
(WinSock) Transmission Control Protocol/Internet Protocol (TCP/IP) communications software interface. ODBC operates independently of CLI.
Teradata CLIv2 for Network-Attached Systems
Teradata CLIv2 for network-attached systems (NAS) is a Teradata proprietary API and library providing an interface between applications on a LAN-connected client and Teradata
Database server. Teradata CLIv2 for NAS can:
Chapter 6: Communication Between the Client and Teradata Database Network Attachment Methods
• Provide an application with a pointer to each of the parcels returned from Teradata Database.
MTDP
MTDP is the interface between Teradata CLIv2 for NAS and MOSI. Functions of MTDP include:
• Session initiation and termination
• Logging, verification, recovery, and restart • Physical input to and output from the server
Note: MTDP does not control session balancing; session balancing on network-attached systems is controlled by Teradata Database Gateway on the server.
MOSI
MOSI is the interface between MTDP and Teradata Database. MOSI is a library of service routines providing operating system independence among clients that access Teradata Database. With MOSI, only one version of MTDP is required to run on all network-attached platforms. MTDP CLI Application 2418B004 Teradata Database MOSI Request Response
Channel Attachment Method
Channel Attachment Method
Channel attachment uses Teradata CLIv2 for channel-attached systems (CAS).
Teradata CLIv2 for Channel-Attached Systems
Teradata CLIv2 for CAS is a collection of callable service routines providing the interface between applications and the Teradata Director Program (TDP) on an IBM mainframe client. Teradata CLIv2 for CAS can operate with all versions of IBM operating systems, including Customer Information Control System (CICS), Information Management System (IMS), and z/OS.
By way of TDP, Teradata CLIv2 for CAS sends requests to the server and provides client applications with responses from the server. Teradata CLIv2 for CAS provides support for:
• Managing multiple serially executed requests in a session
• Managing multiple simultaneous sessions to the same or different servers
• Using cooperative processing so an application can perform operations on the client and the server at the same time
• Communicating with Two-Phase Commit (2PC) coordinators for CICS and IMS transactions
• Generally insulating the application from the details of communicating with a server
Teradata Director Program
TDP manages communications between Teradata CLIv2 for CAS and the Teradata Database server. TDP executes on the same mainframe as Teradata CLIv2 for CAS, but runs as a different job or virtual machine. Although an individual TDP is associated with one logical server, any number of TDPs may operate and be simultaneously accessed by Teradata CLIv2 for CAS on the same mainframe. Each TDP is referred to by an application using an identifier called the TDPid that is unique in a mainframe; for example, TDP2.
Functions of TDP include:
• Session initiation and termination
• Logging, verification, recovery, and restart
• Physical input to and output from the server, including session balancing and queue maintenance
• Security
Teradata Database Server
A server implements the actual relational database that processes requests received from Teradata CLIv2 for CAS by way of TDP. The following figure illustrates the logical structure of the client-server interface on channel-attached systems.
Chapter 6: Communication Between the Client and Teradata Database For More Information
For More Information
For more information on the topics presented in this chapter, see the following Teradata Tools and Utilities books.
Application Program CLIv2 TDP Teradata Database Server TDP Teradata Database Server TDP Teradata Database Server REQUESTS RESPONSES 1091B004
IF you want to learn more about… See…
Network Attachment Methods, including: • .NET Data Provider for Teradata • Teradata CLIv2 for NAS
• Java Database Connectivity, including Java language external stored procedures that use JDBC
• OLE DB Provider for Teradata • Open Database Connectivity
• .NET Data Provider for Teradata Release Definition
• Teradata Call-Level Interface Version 2 Reference for Network-Attached Systems
• Teradata JDBC Driver User Guide
• OLE DB Provider for Teradata Installation and User Guide
• Teradata ODBC Driver User Guide
Channel Attachment Method, including: • Teradata CLIv2 for CAS
• Teradata Director Program
• Teradata Call-Level Interface Version 2 Reference for Channel-Attached Systems