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diff --git a/bdb/docs/ref/transapp/term.html b/bdb/docs/ref/transapp/term.html deleted file mode 100644 index d6d54a44d29..00000000000 --- a/bdb/docs/ref/transapp/term.html +++ /dev/null @@ -1,60 +0,0 @@ -<!--$Id: term.so,v 10.16 2000/08/16 17:50:40 margo Exp $--> -<!--Copyright 1997, 1998, 1999, 2000 by Sleepycat Software, Inc.--> -<!--All rights reserved.--> -<html> -<head> -<title>Berkeley DB Reference Guide: Terminology</title> -<meta name="description" content="Berkeley DB: An embedded database programmatic toolkit."> -<meta name="keywords" content="embedded,database,programmatic,toolkit,b+tree,btree,hash,hashing,transaction,transactions,locking,logging,access method,access methods,java,C,C++"> -</head> -<body bgcolor=white> -<table><tr valign=top> -<td><h3><dl><dt>Berkeley DB Reference Guide:<dd>Transaction Protected Applications</dl></h3></td> -<td width="1%"><a href="../../ref/transapp/why.html"><img src="../../images/prev.gif" alt="Prev"></a><a href="../../ref/toc.html"><img src="../../images/ref.gif" alt="Ref"></a><a href="../../ref/transapp/app.html"><img src="../../images/next.gif" alt="Next"></a> -</td></tr></table> -<p> -<h1 align=center>Terminology</h1> -<p>Here are some definitions that will be helpful in understanding -transactions: -<p><dl compact> -<p><dt>Thread of control<dd>Berkeley DB is indifferent to the type or style of threads being used by the -application, or, for that matter, if threads are being used at all, as -Berkeley DB supports multi-process access. In the Berkeley DB documentation, any -time we refer to a "thread of control", that can be read as a true -thread (one of many in an application's address space), or, a process. -<p><dt>Free-threaded<dd>A Berkeley DB handle that can be used by multiple threads simultaneously -without any application-level synchronization is called free-threaded. -<p><dt>Transaction<dd>A transaction is a one or more operations on one or more databases, that -should be treated as a single unit of work. For example, changes to a -set of databases, where either all of the changes must be applied to -the database(s) or none of them should. Applications specify when each -transaction starts, what database operations are included in it, and -when it ends. -<p><dt>Transaction abort/commit<dd>Every transaction ends by <i>committing</i> or <i>aborting</i>. -If a transaction commits, then Berkeley DB guarantees that any database -changes included in the transaction will never be lost, even after -system or application failure. If a transaction aborts, or is -uncommitted when the system or application fails, then the changes -involved will never appear in the database. -<p><dt>System or application failure<dd>This is the phrase that we will use to describe when something bad -happens near your data. It can be an application dumping core, being -interrupted by a signal, the disk filling up, or the entire system -crashing. In any case, for whatever reason, the application can no -longer make forward progress, and its databases were left in an unknown -state. -<p><dt>Recovery<dd>Whenever system or application failure occurs, the application must run -recovery. Recovery is what makes the database consistent, that is, the -recovery process includes review of log files and databases to ensure -that the changes from each committed transaction appear in the database, -and that no changes from an unfinished (or aborted) transaction do. -<p><dt>Deadlock<dd>Deadlock, in its simplest form, happens when one thread of control owns -resource A, but needs resource B, while another thread of control owns -resource B, but needs resource A. Neither thread of control can make -progress, and so one has to give up and release all of its resources, -at which time the remaining thread of control can make forward progress. -</dl> -<table><tr><td><br></td><td width="1%"><a href="../../ref/transapp/why.html"><img src="../../images/prev.gif" alt="Prev"></a><a href="../../ref/toc.html"><img src="../../images/ref.gif" alt="Ref"></a><a href="../../ref/transapp/app.html"><img src="../../images/next.gif" alt="Next"></a> -</td></tr></table> -<p><font size=1><a href="http://www.sleepycat.com">Copyright Sleepycat Software</a></font> -</body> -</html> |