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| author | Lorry Tar Creator <lorry-tar-importer@baserock.org> | 2015-02-17 17:25:57 +0000 |
|---|---|---|
| committer | <> | 2015-03-17 16:26:24 +0000 |
| commit | 780b92ada9afcf1d58085a83a0b9e6bc982203d1 (patch) | |
| tree | 598f8b9fa431b228d29897e798de4ac0c1d3d970 /docs/programmer_reference/am_conf.html | |
| parent | 7a2660ba9cc2dc03a69ddfcfd95369395cc87444 (diff) | |
| download | berkeleydb-master.tar.gz | |
Diffstat (limited to 'docs/programmer_reference/am_conf.html')
| -rw-r--r-- | docs/programmer_reference/am_conf.html | 163 |
1 files changed, 85 insertions, 78 deletions
diff --git a/docs/programmer_reference/am_conf.html b/docs/programmer_reference/am_conf.html index 1e297bd4..c041c004 100644 --- a/docs/programmer_reference/am_conf.html +++ b/docs/programmer_reference/am_conf.html @@ -14,13 +14,11 @@ <body> <div xmlns="" class="navheader"> <div class="libver"> - <p>Library Version 11.2.5.3</p> + <p>Library Version 12.1.6.1</p> </div> <table width="100%" summary="Navigation header"> <tr> - <th colspan="3" align="center">Chapter 2. - Access Method Configuration - </th> + <th colspan="3" align="center">Chapter 2. Access Method Configuration </th> </tr> <tr> <td width="20%" align="left"><a accesskey="p" href="intro_products.html">Prev</a> </td> @@ -34,9 +32,7 @@ <div class="titlepage"> <div> <div> - <h2 class="title"><a id="am_conf"></a>Chapter 2. - Access Method Configuration - </h2> + <h2 class="title"><a id="am_conf"></a>Chapter 2. Access Method Configuration </h2> </div> </div> </div> @@ -47,36 +43,35 @@ <dl> <dt> <span class="sect1"> - <a href="am_conf.html#am_conf_intro"> - What are the available access methods? - </a> + <a href="am_conf.html#am_conf_intro"> What are the available access + methods? </a> </span> </dt> <dd> <dl> <dt> <span class="sect2"> - <a href="am_conf.html#idm2161896">Btree</a> + <a href="am_conf.html#idm2727912">Btree</a> </span> </dt> <dt> <span class="sect2"> - <a href="am_conf.html#idp32168">Hash</a> + <a href="am_conf.html#idm1674312">Hash</a> </span> </dt> <dt> <span class="sect2"> - <a href="am_conf.html#idm2680320">Heap</a> + <a href="am_conf.html#idm1985432">Heap</a> </span> </dt> <dt> <span class="sect2"> - <a href="am_conf.html#idm2335248">Queue</a> + <a href="am_conf.html#idm1872368">Queue</a> </span> </dt> <dt> <span class="sect2"> - <a href="am_conf.html#idm1801904">Recno</a> + <a href="am_conf.html#idm1924872">Recno</a> </span> </dt> </dl> @@ -90,17 +85,17 @@ <dl> <dt> <span class="sect2"> - <a href="am_conf_select.html#idm1772384">Btree or Heap?</a> + <a href="am_conf_select.html#idm2274400">Btree or Heap?</a> </span> </dt> <dt> <span class="sect2"> - <a href="am_conf_select.html#idm2622384">Hash or Btree?</a> + <a href="am_conf_select.html#idm2915784">Hash or Btree?</a> </span> </dt> <dt> <span class="sect2"> - <a href="am_conf_select.html#idm1789184">Queue or Recno?</a> + <a href="am_conf_select.html#idm2732704">Queue or Recno?</a> </span> </dt> </dl> @@ -139,7 +134,8 @@ </dt> <dt> <span class="sect2"> - <a href="general_am_conf.html#am_conf_malloc">Non-local memory allocation</a> + <a href="general_am_conf.html#am_conf_malloc">Non-local memory + allocation</a> </span> </dt> </dl> @@ -158,7 +154,8 @@ </dt> <dt> <span class="sect2"> - <a href="bt_conf.html#am_conf_bt_prefix">Btree prefix comparison</a> + <a href="bt_conf.html#am_conf_bt_prefix">Btree prefix + comparison</a> </span> </dt> <dt> @@ -180,7 +177,8 @@ </dd> <dt> <span class="sect1"> - <a href="hash_conf.html">Hash access method specific configuration</a> + <a href="hash_conf.html">Hash access method specific + configuration</a> </span> </dt> <dd> @@ -204,7 +202,8 @@ </dd> <dt> <span class="sect1"> - <a href="heap_conf.html">Heap access method specific configuration</a> + <a href="heap_conf.html">Heap access method specific + configuration</a> </span> </dt> <dt> @@ -216,22 +215,26 @@ <dl> <dt> <span class="sect2"> - <a href="rq_conf.html#am_conf_recno">Managing record-based databases</a> + <a href="rq_conf.html#am_conf_recno">Managing record-based + databases</a> </span> </dt> <dt> <span class="sect2"> - <a href="rq_conf.html#am_conf_extentsize">Selecting a Queue extent size</a> + <a href="rq_conf.html#am_conf_extentsize">Selecting a Queue extent + size</a> </span> </dt> <dt> <span class="sect2"> - <a href="rq_conf.html#am_conf_re_source">Flat-text backing files</a> + <a href="rq_conf.html#am_conf_re_source">Flat-text backing + files</a> </span> </dt> <dt> <span class="sect2"> - <a href="rq_conf.html#am_conf_renumber">Logically renumbering records</a> + <a href="rq_conf.html#am_conf_renumber">Logically renumbering + records</a> </span> </dt> </dl> @@ -242,9 +245,8 @@ <div class="titlepage"> <div> <div> - <h2 class="title" style="clear: both"><a id="am_conf_intro"></a> - What are the available access methods? - </h2> + <h2 class="title" style="clear: both"><a id="am_conf_intro"></a> What are the available access + methods? </h2> </div> </div> </div> @@ -252,123 +254,128 @@ <dl> <dt> <span class="sect2"> - <a href="am_conf.html#idm2161896">Btree</a> + <a href="am_conf.html#idm2727912">Btree</a> </span> </dt> <dt> <span class="sect2"> - <a href="am_conf.html#idp32168">Hash</a> + <a href="am_conf.html#idm1674312">Hash</a> </span> </dt> <dt> <span class="sect2"> - <a href="am_conf.html#idm2680320">Heap</a> + <a href="am_conf.html#idm1985432">Heap</a> </span> </dt> <dt> <span class="sect2"> - <a href="am_conf.html#idm2335248">Queue</a> + <a href="am_conf.html#idm1872368">Queue</a> </span> </dt> <dt> <span class="sect2"> - <a href="am_conf.html#idm1801904">Recno</a> + <a href="am_conf.html#idm1924872">Recno</a> </span> </dt> </dl> </div> - <p> - Berkeley DB currently offers five access methods: Btree, Hash, Heap, Queue and Recno. + <p> + Berkeley DB currently offers five access methods: Btree, + Hash, Heap, Queue and Recno. </p> <div class="sect2" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> - <h3 class="title"><a id="idm2161896"></a>Btree</h3> + <h3 class="title"><a id="idm2727912"></a>Btree</h3> </div> </div> </div> - <p> - The Btree access method is an implementation of a sorted, balanced - tree structure. Searches, insertions, and deletions in the tree - all take <span class="emphasis"><em>O(height)</em></span> time, where - <span class="emphasis"><em>height</em></span> is the number of levels in the - Btree from the root to the leaf pages. The upper bound on the - height is <span class="emphasis"><em>log base_b N</em></span>, where - <span class="emphasis"><em>base_b</em></span> is the smallest number of keys on a - page, and <span class="emphasis"><em>N</em></span> is the total number of keys - stored. + <p> + The Btree access method is an implementation of a + sorted, balanced tree structure. Searches, insertions, and + deletions in the tree all take + <span class="emphasis"><em>O(height)</em></span> time, where + <span class="emphasis"><em>height</em></span> is the number of levels in + the Btree from the root to the leaf pages. The upper bound + on the height is <span class="emphasis"><em>log base_b N</em></span>, where + <span class="emphasis"><em>base_b</em></span> is the smallest number of + keys on a page, and <span class="emphasis"><em>N</em></span> is the total + number of keys stored. </p> - <p> - Inserting unordered data into a Btree can result in pages that - are only half-full. DB makes ordered (or inverse ordered) - insertion the best case, resulting in nearly full-page space - utilization. + <p> + Inserting unordered data into a Btree can result in + pages that are only half-full. DB makes ordered (or + inverse ordered) insertion the best case, resulting in + nearly full-page space utilization. </p> </div> <div class="sect2" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> - <h3 class="title"><a id="idp32168"></a>Hash</h3> + <h3 class="title"><a id="idm1674312"></a>Hash</h3> </div> </div> </div> <p> - The Hash access method data structure is an implementation of - Extended Linear Hashing, as described in "Linear Hashing: A New - Tool for File and Table Addressing", Witold Litwin, - <span class="emphasis"><em>Proceedings of the 6th International Conference on Very - Large Databases (VLDB)</em></span>, 1980. + The Hash access method data structure is an + implementation of Extended Linear Hashing, as described in + "Linear Hashing: A New Tool for File and Table + Addressing", Witold Litwin, <span class="emphasis"><em>Proceedings of the + 6th International Conference on Very Large Databases + (VLDB)</em></span>, 1980. </p> </div> <div class="sect2" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> - <h3 class="title"><a id="idm2680320"></a>Heap</h3> + <h3 class="title"><a id="idm1985432"></a>Heap</h3> </div> </div> </div> <p> - The Heap access method stores records in a heap file. Records - are referenced solely by the page and offset at which they are - written. Because records are written in a heap file, compaction - is not necessary when deleting records, which allows for more - efficient use of space than if Btree is in use. The Heap access - method is intended for platforms with constrained disk space, - especially if those systems are performing a great many record - creation and deletions. + The Heap access method stores records in a heap file. + Records are referenced solely by the page and offset at + which they are written. Because records are written in a + heap file, compaction is not necessary when deleting + records, which allows for more efficient use of space than + if Btree is in use. The Heap access method is intended for + platforms with constrained disk space, especially if those + systems are performing a great many record creation and + deletions. </p> </div> <div class="sect2" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> - <h3 class="title"><a id="idm2335248"></a>Queue</h3> + <h3 class="title"><a id="idm1872368"></a>Queue</h3> </div> </div> </div> - <p> - The Queue access method stores fixed-length records with logical - record numbers as keys. It is designed for fast inserts at the - tail and has a special cursor consume operation that deletes and - returns a record from the head of the queue. The Queue access - method uses record level locking. + <p> + The Queue access method stores fixed-length records + with logical record numbers as keys. It is designed for + fast inserts at the tail and has a special cursor consume + operation that deletes and returns a record from the head + of the queue. The Queue access method uses record level + locking. </p> </div> <div class="sect2" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> - <h3 class="title"><a id="idm1801904"></a>Recno</h3> + <h3 class="title"><a id="idm1924872"></a>Recno</h3> </div> </div> </div> <p> - The Recno access method stores both fixed and variable-length - records with logical record numbers as keys, optionally backed by a - flat text (byte stream) file. + The Recno access method stores both fixed and + variable-length records with logical record numbers as + keys, optionally backed by a flat text (byte stream) file. </p> </div> </div> |