diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-05 17:28:19 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-05 17:28:19 +0000 |
commit | 18657a960e125336f704ea058e25c27bd3900dcb (patch) | |
tree | 17b438b680ed45a996d7b59951e6aa34023783f2 /www/dbhash.html | |
parent | Initial commit. (diff) | |
download | sqlite3-upstream.tar.xz sqlite3-upstream.zip |
Adding upstream version 3.40.1.upstream/3.40.1upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'www/dbhash.html')
-rw-r--r-- | www/dbhash.html | 193 |
1 files changed, 193 insertions, 0 deletions
diff --git a/www/dbhash.html b/www/dbhash.html new file mode 100644 index 0000000..1aee868 --- /dev/null +++ b/www/dbhash.html @@ -0,0 +1,193 @@ +<!DOCTYPE html> +<html><head> +<meta name="viewport" content="width=device-width, initial-scale=1.0"> +<meta http-equiv="content-type" content="text/html; charset=UTF-8"> +<link href="sqlite.css" rel="stylesheet"> +<title>The dbhash.exe Utility Program</title> +<!-- path= --> +</head> +<body> +<div class=nosearch> +<a href="index.html"> +<img class="logo" src="images/sqlite370_banner.gif" alt="SQLite" border="0"> +</a> +<div><!-- IE hack to prevent disappearing logo --></div> +<div class="tagline desktoponly"> +Small. Fast. Reliable.<br>Choose any three. +</div> +<div class="menu mainmenu"> +<ul> +<li><a href="index.html">Home</a> +<li class='mobileonly'><a href="javascript:void(0)" onclick='toggle_div("submenu")'>Menu</a> +<li class='wideonly'><a href='about.html'>About</a> +<li class='desktoponly'><a href="docs.html">Documentation</a> +<li class='desktoponly'><a href="download.html">Download</a> +<li class='wideonly'><a href='copyright.html'>License</a> +<li class='desktoponly'><a href="support.html">Support</a> +<li class='desktoponly'><a href="prosupport.html">Purchase</a> +<li class='search' id='search_menubutton'> +<a href="javascript:void(0)" onclick='toggle_search()'>Search</a> +</ul> +</div> +<div class="menu submenu" id="submenu"> +<ul> +<li><a href='about.html'>About</a> +<li><a href='docs.html'>Documentation</a> +<li><a href='download.html'>Download</a> +<li><a href='support.html'>Support</a> +<li><a href='prosupport.html'>Purchase</a> +</ul> +</div> +<div class="searchmenu" id="searchmenu"> +<form method="GET" action="search"> +<select name="s" id="searchtype"> +<option value="d">Search Documentation</option> +<option value="c">Search Changelog</option> +</select> +<input type="text" name="q" id="searchbox" value=""> +<input type="submit" value="Go"> +</form> +</div> +</div> +<script> +function toggle_div(nm) { +var w = document.getElementById(nm); +if( w.style.display=="block" ){ +w.style.display = "none"; +}else{ +w.style.display = "block"; +} +} +function toggle_search() { +var w = document.getElementById("searchmenu"); +if( w.style.display=="block" ){ +w.style.display = "none"; +} else { +w.style.display = "block"; +setTimeout(function(){ +document.getElementById("searchbox").focus() +}, 30); +} +} +function div_off(nm){document.getElementById(nm).style.display="none";} +window.onbeforeunload = function(e){div_off("submenu");} +/* Disable the Search feature if we are not operating from CGI, since */ +/* Search is accomplished using CGI and will not work without it. */ +if( !location.origin || !location.origin.match || !location.origin.match(/http/) ){ +document.getElementById("search_menubutton").style.display = "none"; +} +/* Used by the Hide/Show button beside syntax diagrams, to toggle the */ +function hideorshow(btn,obj){ +var x = document.getElementById(obj); +var b = document.getElementById(btn); +if( x.style.display!='none' ){ +x.style.display = 'none'; +b.innerHTML='show'; +}else{ +x.style.display = ''; +b.innerHTML='hide'; +} +return false; +} +var antiRobot = 0; +function antiRobotGo(){ +if( antiRobot!=3 ) return; +antiRobot = 7; +var j = document.getElementById("mtimelink"); +if(j && j.hasAttribute("data-href")) j.href=j.getAttribute("data-href"); +} +function antiRobotDefense(){ +document.body.onmousedown=function(){ +antiRobot |= 2; +antiRobotGo(); +document.body.onmousedown=null; +} +document.body.onmousemove=function(){ +antiRobot |= 2; +antiRobotGo(); +document.body.onmousemove=null; +} +setTimeout(function(){ +antiRobot |= 1; +antiRobotGo(); +}, 100) +antiRobotGo(); +} +antiRobotDefense(); +</script> +<div class=fancy> +<div class=nosearch> +<div class="fancy_title"> +The dbhash.exe Utility Program +</div> +</div> + + + + +<h1 id="overview"><span>1. </span>Overview</h1> + +<p>The <b>dbhash</b> (or <b>dbhash.exe</b> on Windows) utility is a +command-line program that computes the SHA1 hash of the schema and content +for an SQLite database. + +</p><p>Dbhash ignores extraneous formatting details and hashes only the database +schema and content. Hence the hash is constant even if the database file +is modified by: + +</p><ul> +<li> <a href="lang_vacuum.html">VACUUM</a> +</li><li> <a href="pragma.html#pragma_page_size">PRAGMA page_size</a> +</li><li> <a href="pragma.html#pragma_journal_mode">PRAGMA journal_mode</a> +</li><li> <a href="lang_reindex.html">REINDEX</a> +</li><li> <a href="lang_analyze.html">ANALYZE</a> +</li><li> copied via the <a href="backup.html">backup API</a> +</li><li> ... and so forth +</li></ul> + +<p>The operations above can potentially cause vast changes the raw database file, +and hence cause very different SHA1 hashes at the file level. +But since the content represented in the database file is unchanged by these +operations, the hash computed by dbhash is also unchanged. + +</p><p>Dbhash can be used to compare two databases to confirm that they +are equivalent, even though their representation on disk is quite different. +Dbhash might also be used to verify the content of a remote database without having +to transmit the entire content of the remote database over a slow link. + +</p><h1 id="usage"><span>2. </span>Usage</h1> + +<p>Dbhash is a command-line utility. +To run it, type "dbhash" on a command-line prompt followed by the names of +one or more SQLite database files that are to be hashed. +The database hashes will be displayed on standard output. +For example: + +</p><div class="codeblock"><pre>drh@bella:~/sqlite/bld$ dbhash ~/Fossils/sqlite.fossil +8d3da9ff87196312aaa33076627ccb7943ef79e3 /home/drh/Fossils/sqlite.fossil +</pre></div> + +<p>Dbhash supports command-line options that can restrict the tables of the +database file that are hashed, or restrict the hash to only content or only +the schema. Run "dbhash --help" for further information. + +</p><h1 id="building"><span>3. </span>Building</h1> + +<p>To build a copy of the dbhash utility program on unix, get a copy of the +canonical SQLite source code and enter: + +</p><div class="codeblock"><pre>./configure +make dbhash +</pre></div> + +<p>On Windows, enter: + +</p><div class="codeblock"><pre>nmake /f makefile.msc dbhash.exe +</pre></div> + +<p>The dbhash program is implemented by a single file of C-code +called <a href="https://www.sqlite.org/src/artifact?ci=trunk&filename=tool/dbhash.c">dbhash.c</a>. +To build the dbhash program manually, simply compile the dbhash.c source file +and link it against the SQLite library. +</p><p align="center"><small><i>This page last modified on <a href="https://sqlite.org/docsrc/honeypot" id="mtimelink" data-href="https://sqlite.org/docsrc/finfo/pages/dbhash.in?m=e56508811fb75e69b">2016-07-13 13:57:06</a> UTC </small></i></p> + |