Tabular Data Stream (TDS) is an

application layer An application layer is an abstraction layer that specifies the shared communication protocols and interface methods used by hosts in a communications network. An ''application layer'' abstraction is specified in both the Internet Protocol Su ...

protocol Protocol may refer to: Sociology and politics * Protocol (politics) Protocol originally (in Late Middle English, c. 15th century) meant the minutes or logbook taken at a meeting, upon which an agreement was based. The term now commonly refers to ...

used to transfer data between a

database server A database server is a server which uses a database application that provides database services to other computer programs or to computers, as defined by the client–server model. Database management systems (DBMSs) frequently provide database- ...

and a client. It was initially designed and developed by

Sybase Sybase, Inc. was an enterprise software and services company. The company produced software relating to relational databases, with facilities located in California and Massachusetts. Sybase was acquired by SAP in 2010; SAP ceased using the Syba ...

Inc. for their Sybase SQL Server

relational database A relational database (RDB) is a database based on the relational model of data, as proposed by E. F. Codd in 1970. A Relational Database Management System (RDBMS) is a type of database management system that stores data in a structured for ...

engine in 1984, and later by

Microsoft Microsoft Corporation is an American multinational corporation and technology company, technology conglomerate headquartered in Redmond, Washington. Founded in 1975, the company became influential in the History of personal computers#The ear ...

Microsoft SQL Server Microsoft SQL Server is a proprietary relational database management system developed by Microsoft using Structured Query Language (SQL, often pronounced "sequel"). As a database server, it is a software product with the primary function of ...

History

During the early development of Sybase SQL Server, the developers at Sybase perceived the lack of a commonly accepted application level protocol to transfer data between a

and its

client Client(s) or The Client may refer to: * Client (business) * Client (computing), hardware or software that accesses a remote service on another computer * Customer or client, a recipient of goods or services in return for monetary or other valuable ...

. In order to encourage the use of its products, Sybase promoted the use of a flexible pair of

libraries A library is a collection of Book, books, and possibly other Document, materials and Media (communication), media, that is accessible for use by its members and members of allied institutions. Libraries provide physical (hard copies) or electron ...

, called netlib and db-lib, to implement standard

SQL Structured Query Language (SQL) (pronounced ''S-Q-L''; or alternatively as "sequel") is a domain-specific language used to manage data, especially in a relational database management system (RDBMS). It is particularly useful in handling s ...

. A further library was included in order to implement "Bulk Copy" called blk. While netlib's job is to ferry data between the two computers through the underlying

network protocol A communication protocol is a system of rules that allows two or more entities of a communications system to transmit information via any variation of a physical quantity. The protocol defines the rules, syntax, semantics, and synchronization of ...

, db-lib provides an API to the client program, and communicates with the server via netlib. db-lib sends to the server a structured stream of bytes meant for tables of data, hence a Tabular Data Stream. blk provides, like db-lib, an API to the client programs and communicates with the server via netlib. In 1990 Sybase entered into a technology-sharing agreement with

which resulted in Microsoft marketing its own SQL Server —

— based on Sybase's code. Microsoft kept the db-lib API and added

ODBC In computing, Open Database Connectivity (ODBC) is a standard application programming interface (API) for accessing database management systems (DBMS). The designers of ODBC aimed to make it independent of database systems and operating systems. An ...

. (Microsoft has since added additional APIs.) At about the same time, Sybase introduced a more powerful successor to db-lib, called ct-lib, and called the pair

Open Client Open or OPEN may refer to: Music * Open (band), Australian pop/rock band * The Open (band), English indie rock band * ''Open'' (Blues Image album), 1969 * ''Open'' (Gerd Dudek, Buschi Niebergall, and Edward Vesala album), 1979 * ''Open'' (Got ...

. db-lib, though officially deprecated, remains in widespread use. The TDS protocol comes in several varieties, most of which had not been openly documented because they were regarded as proprietary technology. The exception was TDS 5.0, used exclusively by Sybase, for which documentation is available from Sybase. This situation changed when Microsoft published the TDS specification in 2008, as part of the

Open Specification Promise The Microsoft Open Specification Promise (or OSP) is a promise by Microsoft, published in September 2006, to not assert its patents, in certain conditions, against implementations of a certain list of specifications. The OSP is not a licence, but ...

. The FreeTDS team has developed a free native-library implementation of the TDS protocol, licensed under the

LGPL The GNU Lesser General Public License (LGPL) is a free-software license published by the Free Software Foundation (FSF). The license allows developers and companies to use and integrate a software component released under the LGPL into their own ...

license.

WireShark Wireshark is a Free and open-source software, free and open-source packet analyzer. It is used for computer network, network troubleshooting, analysis, software and communications protocol development, and education. Originally named Ethereal, ...

has a protocol decoder for TDS.

Oracle Corporation Oracle Corporation is an American Multinational corporation, multinational computer technology company headquartered in Austin, Texas. Co-founded in 1977 in Santa Clara, California, by Larry Ellison, who remains executive chairman, Oracle was ...

provides Oracle Net - software analogous to TDS.

References

{{reflist

JDBC Java Database Connectivity (JDBC) is an application programming interface (API) for the Java (programming language), Java programming language which defines how a client may access a database. It is a Java-based data access technology used for Java ...

driver for TDS databases
jBCP
an extension of jTDS to include BCP protocols

Microsoft
Patent: TRANSPORTING TABLE VALUED PARAMETER OVER TABULAR DATA STREAM PROTOCOL
Microsoft
Patent application: COMPRESSING NULL COLUMNS IN ROWS OF THE TABULAR DATA STREAM PROTOCOL
Microsoft
WireShark wiki: Protocol tds
Application layer protocols Database access protocols

History

See also

References

External links