Many hyperlinks are disabled.
Use anonymous login
to enable hyperlinks.
Overview
Comment: | Add incomplete, preliminary drafts of new documentation. (CVS 2225) |
---|---|
Downloads: | Tarball | ZIP archive |
Timelines: | family | ancestors | descendants | both | trunk |
Files: | files | file ages | folders |
SHA1: |
a01159e8cb93199763d191b739da2a43 |
User & Date: | drh 2005-01-17 03:42:52.000 |
Context
2005-01-17
| ||
07:53 | Fix some memory leak problems with corrupt.test and auto-vacuum databases. (CVS 2226) (check-in: 6244252915 user: danielk1977 tags: trunk) | |
03:42 | Add incomplete, preliminary drafts of new documentation. (CVS 2225) (check-in: a01159e8cb user: drh tags: trunk) | |
03:40 | Fix a memory leak that occurs as a result of an IO error. (CVS 2224) (check-in: 1edfdcbf14 user: danielk1977 tags: trunk) | |
Changes
Added www/different.tcl.
> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 | set rcsid {$Id: different.tcl,v 1.1 2005/01/17 03:42:52 drh Exp $} source common.tcl header {Distinctive Features Of SQLite} puts { <p> This page highlights some of the characteristics of SQLite that are unusual and which make SQLite different from many other SQL database engines. </p> } proc feature {tag name text} { puts "<a name=\"$tag\" />" puts "<p><b>$name</b></p>\n" puts "<blockquote>$text</blockquote>\n" } feature zeroconfig {Zero-Configuration} { SQLite does not need to be "installed" before it is used. There is no "setup" procedure. There is no server process that needs to be started, stopped, or configured. There is no need for an administrator to create a new database instance or assign access permissions to users. SQLite uses no configuration files. Nothing needs to be done to tell the system that SQLite is running. No actions are required to recover after a system crash or power failure. There is nothing to troubleshoot. <p> SQLite just works. <p> An SQLite database is an ordinary disk file. If SQLite can read the disk file then it can read anything in the database. If the disk file and its directory are writable, then SQLite can change anything in the database. } feature serverless {Serverless} { Most SQL database engines are implemented as a separate server process. Programs that want to access the database communicate with the server using some kind of interprocess communcation (typically TCP/IP) to send requests to the server and to receive back results. SQLite does not work this way. With SQLite, the process that wants to access the database reads and writes directly from the database files on disk. There is no intermediary server process. <p> There are advantages and disadvantages to being serverless. The main advantage is that there is no separate server process to install, setup, configure, initialize, manage, and troubleshoot. This is one reason why SQLite is a "zero-configuration" database engine. Programs that use SQLite require no administrative support for setting up the database engine before they are run. Any program that is able to access the disk is able to use an SQLite database. <p> On the other hand, a database engine that uses a server can provide better protection from bugs in the client application - stray pointers in a client cannot corrupt memory on the server. And because a server is a single persistent process, it is able control database access with more precision, allowing for finer grain locking and better concurrancy. <p> Most SQL database engines are client/server based. Of those that are serverless, SQLite is the only one that this author knows of that allows multiple applications to access the same database at the same time. } feature small {Compact} { When optimized for size, the whole SQLite library with everything enabled is less than 220KiB in size (as measured on an ix86 using the "size" utility from the GNU compiler suite.) Unneeded features can be disabled at compile-time to further reduce the size of the library to under 180KiB if desired. <p> Most other SQL database engines are much larger than this. IBM boasts that it's recently released CloudScape database engine is "only" a 2MiB jar file - 10 times larger than SQLite even after it is compressed! Firefox boasts that it's client-side library is only 350KiB. That's 50% larger than SQLite and does not even contain the database engine. The Berkeley DB library from Sleepycat is 450KiB and it lacks a schema layer. } feature typing {Manifest typing} { } feature readable {Readable source code} { } feature vdbe {SQL statements compile into virtual machine code} { } feature binding {Tight bindings to dynamic languages} { } feature license {Public domain} { The source code for SQLite is in the public domain. No claim of copyright is made on any part of the core source code. (The documentation and test code is a different matter - some sections of documentation and test logic are governed by open-sources licenses.) All contributors to the SQLite core software have signed releases specifically disavowing any copyright interest in the code. This means that anybody is able to legally do anything they want with the SQLite source code. <p> There are other SQL database engines with liberal licenses that allow the code to be broadly and freely used. But those other engines are still governed by copyright law. SQLite is different in that copyright law simply does not apply. <p> The source code files for other SQL database engines typically begin with a comment describing your license rights to view and copy that file. The SQLite source code contains no license since it is not governed by copyright. Instead of a license, the SQLite source code offers a blessing: <blockquote> <i>May you do good and not evil<br> May you find forgiveness for yourself and forgive others<br> May you share freely, never taking more than you give.</i> </blockquote> } feature extensions {SQL language extensions} { } footer $rcsid |
Added www/optimizing.tcl.
> > > > > > > > > > > > > > > | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 | set rcsid {$Id: optimizing.tcl,v 1.1 2005/01/17 03:42:52 drh Exp $} source common.tcl header {Hints For Optimizing Queries In SQLite} proc section {level tag name} { incr level if {$level>6} {set level 6} puts "\n"<a name=\"tag\" />" puts "<h$level>$name</h$level>\n" } section 1 recompile {Recompile the library for optimal performance} section 2 avoidtrans {Minimize the number of transactions} section 3 usebind {Use sqlite3_bind to insert large chunks of data} section 4 useindices {Use appropriate indices} section 5 recordjoin {Reorder the tables in a join} footer $rcsid |