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diff --git a/bdb/docs/api_cxx/db_set_flags.html b/bdb/docs/api_cxx/db_set_flags.html deleted file mode 100644 index 059810357ec..00000000000 --- a/bdb/docs/api_cxx/db_set_flags.html +++ /dev/null @@ -1,183 +0,0 @@ -<!--$Id: db_set_flags.so,v 10.26 2000/03/17 01:53:58 bostic Exp $--> -<!--Copyright 1997, 1998, 1999, 2000 by Sleepycat Software, Inc.--> -<!--All rights reserved.--> -<html> -<head> -<title>Berkeley DB: Db::set_flags</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> - <a name="2"><!--meow--></a> -<table><tr valign=top> -<td> -<h1>Db::set_flags</h1> -</td> -<td width="1%"> -<a href="../api_cxx/cxx_index.html"><img src="../images/api.gif" alt="API"></a><a href="../ref/toc.html"><img src="../images/ref.gif" alt="Ref"></a> -</td></tr></table> -<hr size=1 noshade> -<tt> -<h3><pre> -#include <db_cxx.h> -<p> -int -Db::set_flags(u_int32_t flags); -</pre></h3> -<h1>Description</h1> -<p>Calling Db::set_flags is additive, there is no way to clear flags. -<p>The <b>flags</b> value must be set to 0 or by bitwise inclusively <b>OR</b>'ing together one or more -of the following values. -<h3>Btree</h3> -<p>The following flags may be specified for the Btree access method: -<p><dl compact> -<p><dt><a name="DB_DUP">DB_DUP</a><dd>Permit duplicate data items in the tree, i.e. insertion when the key of -the key/data pair being inserted already exists in the tree will be -successful. The ordering of duplicates in the tree is determined by the -order of insertion, unless the ordering is otherwise specified by use of -a cursor operation. It is an error to specify both DB_DUP and -DB_RECNUM. -<p><dt><a name="DB_DUPSORT">DB_DUPSORT</a><dd>Permit duplicate data items in the tree, i.e. insertion when the key of -the key/data pair being inserted already exists in the tree will be -successful. The ordering of duplicates in the tree is determined by the -duplicate comparison function. -If the application does not specify a comparison function using the -<a href="../api_cxx/db_set_dup_compare.html">Db::set_dup_compare</a> method, a default, lexical comparison will be -used. -It is an error to specify both DB_DUPSORT and DB_RECNUM. -<p><dt><a name="DB_RECNUM">DB_RECNUM</a><dd>Support retrieval from the Btree using record numbers. For more -information, see the DB_GET_RECNO flag to the <a href="../api_cxx/db_get.html">Db::get</a> and -<a href="../api_cxx/dbc_get.html">Dbc::get</a> methods. -<p>Logical record numbers in Btree databases are mutable in the face of -record insertion or deletion. See the DB_RENUMBER flag in the Recno -access method information for further discussion. -<p>Maintaining record counts within a Btree introduces a serious point of -contention, namely the page locations where the record counts are stored. -In addition, the entire tree must be locked during both insertions and -deletions, effectively single-threading the tree for those operations. -Specifying DB_RECNUM can result in serious performance degradation for -some applications and data sets. -<p>It is an error to specify both DB_DUP and DB_RECNUM. -<p><dt><a name="DB_REVSPLITOFF">DB_REVSPLITOFF</a><dd>Turn off reverse splitting in the Btree. As pages are emptied in a -database, the Berkeley DB Btree implementation attempts to coalesce empty pages -into higher-level pages in order to keep the tree as small as possible -and minimize tree search time. This can hurt performance in applications -with cyclical data demands, that is, applications where the database grows -and shrinks repeatedly. For example, because Berkeley DB does page-level -locking, the maximum level of concurrency in a database of 2 pages is far -smaller than that in a database of 100 pages, and so a database that has -shrunk to a minimal size can cause severe deadlocking when a new cycle of -data insertion begins. -</dl> -<h3>Hash</h3> -<p>The following flags may be specified for the Hash access method: -<p><dl compact> -<p><dt><a name="DB_DUP">DB_DUP</a><dd>Permit duplicate data items in the tree, i.e. insertion when the key of -the key/data pair being inserted already exists in the tree will be -successful. The ordering of duplicates in the tree is determined by the -order of insertion, unless the ordering is otherwise specified by use of -a cursor operation. It is an error to specify both DB_DUP and -DB_RECNUM. -<p><dt><a name="DB_DUPSORT">DB_DUPSORT</a><dd>Permit duplicate data items in the tree, i.e. insertion when the key of -the key/data pair being inserted already exists in the tree will be -successful. The ordering of duplicates in the tree is determined by the -duplicate comparison function. -If the application does not specify a comparison function using the -<a href="../api_cxx/db_set_dup_compare.html">Db::set_dup_compare</a> method, a default, lexical comparison will be -used. -It is an error to specify both DB_DUPSORT and DB_RECNUM. -</dl> -<h3>Queue</h3> -<p>There are no additional flags that may be specified for the Queue access -method. -<h3>Recno</h3> -<p>The following flags may be specified for the Recno access method: -<p><dl compact> -<p><dt><a name="DB_RENUMBER">DB_RENUMBER</a><dd>Specifying the DB_RENUMBER flag causes the logical record numbers to be -mutable, and change as records are added to and deleted from the database. -For example, the deletion of record number 4 causes records numbered 5 -and greater to be renumbered downward by 1. If a cursor was positioned -to record number 4 before the deletion, it will reference the new record -number 4, if any such record exists, after the deletion. If a cursor was -positioned after record number 4 before the deletion, it will be shifted -downward 1 logical record, continuing to reference the same record as it -did before. -<p>Using the <a href="../api_cxx/db_put.html">Db::put</a> or <a href="../api_cxx/dbc_put.html">Dbc::put</a> interfaces to create new -records will cause the creation of multiple records if the record number -is more than one greater than the largest record currently in the -database. For example, creating record 28, when record 25 was previously -the last record in the database, will create records 26 and 27 as well as -28. Attempts to retrieve records that were created in this manner will -result in an error return of <a href="../ref/program/errorret.html#DB_KEYEMPTY">DB_KEYEMPTY</a>. -<p>If a created record is not at the end of the database, all records -following the new record will be automatically renumbered upward by 1. -For example, the creation of a new record numbered 8 causes records -numbered 8 and greater to be renumbered upward by 1. If a cursor was -positioned to record number 8 or greater before the insertion, it will be -shifted upward 1 logical record, continuing to reference the same record -as it did before. -<p>For these reasons, concurrent access to a Recno database with the -DB_RENUMBER flag specified may be largely meaningless, although -it is supported. -<p><dt><a name="DB_SNAPSHOT">DB_SNAPSHOT</a><dd>This flag specifies that any specified <b>re_source</b> file be read in -its entirety when <a href="../api_cxx/db_open.html">Db::open</a> is called. If this flag is not -specified, the <b>re_source</b> file may be read lazily. -</dl> -<p>The Db::set_flags interface may only be used to configure Berkeley DB before -the <a href="../api_cxx/db_open.html">Db::open</a> interface is called. -<p>The Db::set_flags method either returns a non-zero error value or throws an exception that -encapsulates a non-zero error value on failure, and returns 0 on success. -<h1>Errors</h1> -<p><dl compact> -<p><dt>EINVAL<dd>An invalid flag value or parameter was specified. -</dl> -<h3>Class</h3> -<a href="../api_cxx/db_class.html">Db</a> -<h1>See Also</h1> -<a href="../api_cxx/db_close.html">Db::close</a>, -<a href="../api_cxx/db_cursor.html">Db::cursor</a>, -<a href="../api_cxx/db_del.html">Db::del</a>, -<a href="../api_cxx/db_err.html">Db::err</a>, -<a href="../api_cxx/db_fd.html">Db::fd</a>, -<a href="../api_cxx/db_get.html">Db::get</a>, -<a href="../api_cxx/db_get_byteswapped.html">Db::get_byteswapped</a>, -<a href="../api_cxx/db_get_type.html">Db::get_type</a>, -<a href="../api_cxx/db_join.html">Db::join</a>, -<a href="../api_cxx/db_key_range.html">Db::key_range</a>, -<a href="../api_cxx/db_open.html">Db::open</a>, -<a href="../api_cxx/db_put.html">Db::put</a>, -<a href="../api_cxx/db_remove.html">Db::remove</a>, -<a href="../api_cxx/db_set_bt_compare.html">Db::set_bt_compare</a>, -<a href="../api_cxx/db_set_bt_minkey.html">Db::set_bt_minkey</a>, -<a href="../api_cxx/db_set_bt_prefix.html">Db::set_bt_prefix</a>, -<a href="../api_cxx/db_set_cachesize.html">Db::set_cachesize</a>, -<a href="../api_cxx/db_set_dup_compare.html">Db::set_dup_compare</a>, -<a href="../api_cxx/db_set_errcall.html">Db::set_errcall</a>, -<a href="../api_cxx/db_set_errfile.html">Db::set_errfile</a>, -<a href="../api_cxx/db_set_errpfx.html">Db::set_errpfx</a>, -<a href="../api_cxx/db_set_flags.html">Db::set_flags</a>, -<a href="../api_cxx/db_set_h_ffactor.html">Db::set_h_ffactor</a>, -<a href="../api_cxx/db_set_h_hash.html">Db::set_h_hash</a>, -<a href="../api_cxx/db_set_h_nelem.html">Db::set_h_nelem</a>, -<a href="../api_cxx/db_set_lorder.html">Db::set_lorder</a>, -<a href="../api_cxx/db_set_malloc.html">Db::set_malloc</a>, -<a href="../api_cxx/db_set_pagesize.html">Db::set_pagesize</a>, -<a href="../api_cxx/db_set_paniccall.html">Db::set_paniccall</a>, -<a href="../api_cxx/db_set_q_extentsize.html">Db::set_q_extentsize</a>, -<a href="../api_cxx/db_set_realloc.html">Db::set_realloc</a>, -<a href="../api_cxx/db_set_re_delim.html">Db::set_re_delim</a>, -<a href="../api_cxx/db_set_re_len.html">Db::set_re_len</a>, -<a href="../api_cxx/db_set_re_pad.html">Db::set_re_pad</a>, -<a href="../api_cxx/db_set_re_source.html">Db::set_re_source</a>, -<a href="../api_cxx/db_stat.html">Db::stat</a>, -<a href="../api_cxx/db_sync.html">Db::sync</a>, -<a href="../api_cxx/db_upgrade.html">Db::upgrade</a> -and -<a href="../api_cxx/db_verify.html">Db::verify</a>. -</tt> -<table><tr><td><br></td><td width="1%"> -<a href="../api_cxx/cxx_index.html"><img src="../images/api.gif" alt="API"></a><a href="../ref/toc.html"><img src="../images/ref.gif" alt="Ref"></a> -</td></tr></table> -<p><font size=1><a href="http://www.sleepycat.com">Copyright Sleepycat Software</a></font> -</body> -</html> |