Sophie: freetds-doc-0.91-8.mga5 x86

freetds-doc-0.91-8.mga5.x86_64.rpm

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<HTML
><HEAD
><TITLE
>What is FreeTDS?</TITLE
><META
NAME="GENERATOR"
CONTENT="Modular DocBook HTML Stylesheet Version 1.79"><LINK
REL="HOME"
TITLE="FreeTDS User Guide"
HREF="index.htm"><LINK
REL="PREVIOUS"
TITLE="About this User Guide"
HREF="about.htm"><LINK
REL="NEXT"
TITLE="History of TDS Versions"
HREF="tdshistory.htm"><LINK
REL="STYLESHEET"
TYPE="text/css"
HREF="userguide.css"><META
HTTP-EQUIV="Content-Type"
CONTENT="text/html; charset=utf-8"></HEAD
><BODY
CLASS="CHAPTER"
BGCOLOR="#FFFFFF"
TEXT="#000000"
LINK="#0000FF"
VLINK="#840084"
ALINK="#0000FF"
><DIV
CLASS="NAVHEADER"
><TABLE
SUMMARY="Header navigation table"
WIDTH="100%"
BORDER="0"
CELLPADDING="0"
CELLSPACING="0"
><TR
><TH
COLSPAN="3"
ALIGN="center"
><SPAN
CLASS="PRODUCTNAME"
>FreeTDS</SPAN
> User Guide: A Guide to Installing, Configuring, and Running <SPAN
CLASS="PRODUCTNAME"
>FreeTDS</SPAN
></TH
></TR
><TR
><TD
WIDTH="10%"
ALIGN="left"
VALIGN="bottom"
><A
HREF="about.htm"
ACCESSKEY="P"
>Prev</A
></TD
><TD
WIDTH="80%"
ALIGN="center"
VALIGN="bottom"
></TD
><TD
WIDTH="10%"
ALIGN="right"
VALIGN="bottom"
><A
HREF="tdshistory.htm"
ACCESSKEY="N"
>Next</A
></TD
></TR
></TABLE
><HR
ALIGN="LEFT"
WIDTH="100%"></DIV
><DIV
CLASS="CHAPTER"
><H1
><A
NAME="WHAT"
></A
>Chapter 1. What is <SPAN
CLASS="PRODUCTNAME"
>FreeTDS</SPAN
>?</H1
><DIV
CLASS="TOC"
><DL
><DT
><B
>Table of Contents</B
></DT
><DT
><A
HREF="what.htm#TDSPROTOCOLHIST"
>Background: The <ACRONYM
CLASS="ACRONYM"
>TDS</ACRONYM
> Protocol
			and related <ACRONYM
CLASS="ACRONYM"
>API</ACRONYM
>s</A
></DT
><DT
><A
HREF="tdshistory.htm"
>History of <ACRONYM
CLASS="ACRONYM"
>TDS</ACRONYM
> Versions</A
></DT
><DT
><A
HREF="freetdshistory.htm"
>History of <SPAN
CLASS="PRODUCTNAME"
>FreeTDS</SPAN
></A
></DT
><DT
><A
HREF="projects.htm"
>Current Projects, Language Bindings, and Alternatives</A
></DT
></DL
></DIV
><P
><SPAN
CLASS="PRODUCTNAME"
>FreeTDS</SPAN
> is re-implementation of C libraries originally marketed by Sybase and Microsoft SQL Server.  It allows many open source applications such as <SPAN
CLASS="PRODUCTNAME"
>Perl</SPAN
> and <SPAN
CLASS="PRODUCTNAME"
>PHP</SPAN
> (or your own C or C++ program) to connect to Sybase or Microsoft <SPAN
CLASS="PRODUCTNAME"
>SQL Server</SPAN
>.  </P
><P
><SPAN
CLASS="PRODUCTNAME"
>FreeTDS</SPAN
> provides drop-in replacements for 

<P
></P
><UL
><LI
><P
>Sybase's <SPAN
CLASS="SYSTEMITEM"
>DB-Library</SPAN
> and <SPAN
CLASS="SYSTEMITEM"
>CT-Library</SPAN
></P
></LI
><LI
><P
>Microsoft's <SPAN
CLASS="SYSTEMITEM"
>DB-Library</SPAN
> (which differs in small details from Sybase's)</P
></LI
><LI
><P
>the <SPAN
CLASS="SYSTEMITEM"
>ODBC</SPAN
> drivers from both vendors</P
></LI
><LI
><P
>interactive SQL and BCP utilities</P
></LI
></UL
>

The <SPAN
CLASS="QUOTE"
>"TDS"</SPAN
> part of the name comes from name of the protocol used to communicate with such servers: the Tabular Data Stream.  </P
><P
><SPAN
CLASS="PRODUCTNAME"
>FreeTDS</SPAN
> is distributed in source code form, and is expected to compile on just about any operating system.  That means every form of Unix&reg; and Unix-like&trade; system (including notable variants such as Interix&reg; and QNX&reg;), as well as Win32&reg;, VMS&reg;, and OS X&reg;.  If it doesn't compile on your system &mdash; and you're not using MS-DOS&reg; &mdash; it's probably considered a bug.</P
><DIV
CLASS="SECT1"
><H1
CLASS="SECT1"
><A
NAME="TDSPROTOCOLHIST"
>Background: The <ACRONYM
CLASS="ACRONYM"
>TDS</ACRONYM
> Protocol
			and related <ACRONYM
CLASS="ACRONYM"
>API</ACRONYM
>s</A
></H1
><P
><ACRONYM
CLASS="ACRONYM"
>TDS</ACRONYM
> is a <I
CLASS="FIRSTTERM"
>protocol</I
>, a set of rules describing how to transmit data between two computers.  Like any protocol, it defines the types of messages that can be sent, and the order in which they may be sent.  Protocols describe the <SPAN
CLASS="QUOTE"
>"bits on the wire"</SPAN
>, how data flow.</P
><P
>In reading this manual, it may be helpful to keep in mind that a protocol is not an <ACRONYM
CLASS="ACRONYM"
>API</ACRONYM
>, although the two are related.  The server recognizes and speaks a protocol; anything that can send it the correct combination of bytes in the right order can communicate with it.  But programmers aren't generally in the business of sending bytes; that's the job of a library.  Over the years, there have been a few libraries &mdash; each with its own <ACRONYM
CLASS="ACRONYM"
>API</ACRONYM
> &mdash; that do the work of moving SQL through a <ACRONYM
CLASS="ACRONYM"
>TDS</ACRONYM
> pipe.  <SPAN
CLASS="SYSTEMITEM"
>ODBC</SPAN
>, <SPAN
CLASS="SYSTEMITEM"
>DB-Library</SPAN
>, and <SPAN
CLASS="SYSTEMITEM"
>CT-Library</SPAN
> have very different <ACRONYM
CLASS="ACRONYM"
>API</ACRONYM
>s, but they're all one to the server, because on the wire they speak <ACRONYM
CLASS="ACRONYM"
>TDS</ACRONYM
>.</P
><P
>The <ACRONYM
CLASS="ACRONYM"
>TDS</ACRONYM
> protocol was designed and developed by Sybase Inc. for their Sybase <SPAN
CLASS="PRODUCTNAME"
>SQL Server</SPAN
> relational database engine in 1984.  The problem Sybase faced then still exists: There was no commonly accepted application-level protocol to transfer data between a database server and its client.  To encourage the use of their product, Sybase came up with <SPAN
CLASS="SYSTEMITEM"
>DB-Library</SPAN
>.</P
><P
><SPAN
CLASS="SYSTEMITEM"
>DB-Library</SPAN
> provided an <ACRONYM
CLASS="ACRONYM"
>API</ACRONYM
> to the client program, and communicated with the server.  What it sent to the server took the form of a stream of bytes meant for tables of data, a Tabular Data Stream.</P
><P
>In 1990 Sybase entered into a technology sharing agreement with Microsoft which resulted in Microsoft marketing its own <SPAN
CLASS="PRODUCTNAME"
>SQL Server</SPAN
>. Microsoft kept the <SPAN
CLASS="SYSTEMITEM"
>DB-Library</SPAN
> <ACRONYM
CLASS="ACRONYM"
>API</ACRONYM
> and added <SPAN
CLASS="SYSTEMITEM"
>ODBC</SPAN
>.  (Microsoft has since added other <ACRONYM
CLASS="ACRONYM"
>API</ACRONYM
>s, too.  It no longer supports its own <SPAN
CLASS="SYSTEMITEM"
>DB-Library</SPAN
> implementation.) At about the same time, Sybase introduced a more powerful <SPAN
CLASS="QUOTE"
>"successor"</SPAN
> to <SPAN
CLASS="SYSTEMITEM"
>DB-Library</SPAN
>, called <SPAN
CLASS="SYSTEMITEM"
>CT-Library</SPAN
>, and called the pair <SPAN
CLASS="PRODUCTNAME"
><I
CLASS="FIRSTTERM"
>OpenClient</I
></SPAN
>.</P
><P
><SPAN
CLASS="SYSTEMITEM"
>CT-Library</SPAN
>, <SPAN
CLASS="SYSTEMITEM"
>DB-Library</SPAN
>, and <SPAN
CLASS="SYSTEMITEM"
>ODBC</SPAN
> are <ACRONYM
CLASS="ACRONYM"
>API</ACRONYM
>s that &mdash; however different their programming style may be &mdash; all communicate with the server in the same way.  The language they use is <ACRONYM
CLASS="ACRONYM"
>TDS</ACRONYM
>.</P
><P
>The <ACRONYM
CLASS="ACRONYM"
>TDS</ACRONYM
> protocol comes in several flavors, most of which were not openly documented.  If anything, it was considered to be something like a trade secret, or at least proprietary technology.  The exception is <ACRONYM
CLASS="ACRONYM"
>TDS</ACRONYM
> 5.0, used exclusively by Sybase, for which documentation is available <A
HREF="http://crm.sybase.com/sybase/www/ESD/tds_spec_download.jsp"
TARGET="_top"
>from Sybase</A
>.</P
></DIV
></DIV
><DIV
CLASS="NAVFOOTER"
><HR
ALIGN="LEFT"
WIDTH="100%"><TABLE
SUMMARY="Footer navigation table"
WIDTH="100%"
BORDER="0"
CELLPADDING="0"
CELLSPACING="0"
><TR
><TD
WIDTH="33%"
ALIGN="left"
VALIGN="top"
><A
HREF="about.htm"
ACCESSKEY="P"
>Prev</A
></TD
><TD
WIDTH="34%"
ALIGN="center"
VALIGN="top"
><A
HREF="index.htm"
ACCESSKEY="H"
>Home</A
></TD
><TD
WIDTH="33%"
ALIGN="right"
VALIGN="top"
><A
HREF="tdshistory.htm"
ACCESSKEY="N"
>Next</A
></TD
></TR
><TR
><TD
WIDTH="33%"
ALIGN="left"
VALIGN="top"
>About this User Guide</TD
><TD
WIDTH="34%"
ALIGN="center"
VALIGN="top"
>&nbsp;</TD
><TD
WIDTH="33%"
ALIGN="right"
VALIGN="top"
>History of <ACRONYM
CLASS="ACRONYM"
>TDS</ACRONYM
> Versions</TD
></TR
></TABLE
></DIV
></BODY
></HTML
>