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diff --git a/bdb/docs/api_java/db_stat.html b/bdb/docs/api_java/db_stat.html deleted file mode 100644 index 197ba19138d..00000000000 --- a/bdb/docs/api_java/db_stat.html +++ /dev/null @@ -1,185 +0,0 @@ -<!--$Id: db_stat.so,v 10.37 2000/10/03 21:55:45 bostic Exp $--> -<!--Copyright 1997, 1998, 1999, 2000 by Sleepycat Software, Inc.--> -<!--All rights reserved.--> -<html> -<head> -<title>Berkeley DB: Db.stat</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.stat</h1> -</td> -<td width="1%"> -<a href="../api_java/java_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> -import com.sleepycat.db.*; -<p> -public Object Db.stat(int flags); -</pre></h3> -<h1>Description</h1> -<p>The Db.stat method creates a statistical structure and -fills it with statistics for the database. -<p>Statistical structures are created in allocated memory. If <b>db_malloc</b> is non-NULL, it -is called to allocate the memory, otherwise, the library function -<b>malloc</b>(3) is used. The function <b>db_malloc</b> must match -the calling conventions of the <b>malloc</b>(3) library routine. -Regardless, the caller is responsible for deallocating the returned -memory. To deallocate returned memory, free the returned memory -reference, references inside the returned memory do not need to be -individually freed. -<p>The <b>flags</b> parameter must be set to 0 or the following value: -<p><dl compact> -<p><dt><a name="Db.DB_CACHED_COUNTS">Db.DB_CACHED_COUNTS</a><dd>Return a cached count of the keys and records in a database. This flag -makes it possible for applications to request an possibly approximate key -and record count without incurring the performance penalty of traversing -the entire database. The statistics information described for the access -method <b>XX_nkeys</b> and <b>XX_ndata</b> fields below is filled in, -but no other information is collected. If the cached information has -never been set, the fields will be returned set to 0. -<p><dt><a name="Db.DB_RECORDCOUNT">Db.DB_RECORDCOUNT</a><dd>Return a count of the records in a Btree or Recno Access Method database. -This flag makes it possible for applications to request a record count -without incurring the performance penalty of traversing the entire -database. The statistics information described for the <b>bt_nkeys</b> -field below is filled in, but no other information is collected. -<p>This option is only available for Recno databases, or Btree databases -where the underlying database was created with the <a href="../api_java/db_set_flags.html#DB_RECNUM">Db.DB_RECNUM</a> -flag. -</dl> -<p>The Db.stat method may access all of the pages in the database, -incurring a severe performance penalty as well as possibly flushing the -underlying buffer pool. -<p>In the presence of multiple threads or processes accessing an active -database, the information returned by Db.stat may be out-of-date. -<p>If the database was not opened readonly and the Db.DB_CACHED_COUNTS -flag was not specified, the cached key and record numbers will be updated -after the statistical information has been gathered. -<p>The Db.stat method cannot be transaction protected. For this reason, -it should be called in a thread of control that has no open cursors or -active transactions. -<p>The Db.stat method throws an exception that encapsulates a non-zero error value on -failure. -<h3>Hash Statistics</h3> -<p>In the case of a Hash database, -the statistics are returned in an instance of DbHashStat. The data -fields are available from DbHashStat: -<p><dl compact> -<p><dt>public int hash_magic;<dd>Magic number that identifies the file as a Hash file. -<dt>public int hash_version;<dd>The version of the Hash database. -<dt>public int hash_nkeys;<dd>The number of unique keys in the database. -<dt>public int hash_ndata;<dd>The number of key/data pairs in the database.] -<dt>public int hash_pagesize;<dd>The underlying Hash database page (and bucket) size. -<dt>public int hash_nelem;<dd>The estimated size of the hash table specified at database creation time. -<dt>public int hash_ffactor;<dd>The desired fill factor (number of items per bucket) specified at database -creation time. -<dt>public int hash_buckets;<dd>The number of hash buckets. -<dt>public int hash_free;<dd>The number of pages on the free list. -<dt>public int hash_bfree;<dd>The number of bytes free on bucket pages. -<dt>public int hash_bigpages;<dd>The number of big key/data pages. -<dt>public int hash_big_bfree;<dd>The number of bytes free on big item pages. -<dt>public int hash_overflows;<dd>The number of overflow pages (overflow pages are pages that contain items -that did not fit in the main bucket page). -<dt>public int hash_ovfl_free;<dd>The number of bytes free on overflow pages. -<dt>public int hash_dup;<dd>The number of duplicate pages. -<dt>public int hash_dup_free;<dd>The number of bytes free on duplicate pages. -</dl> -<h3>Btree and Recno Statistics</h3> -<p>In the case of a Btree or Recno database, -the statistics are returned in an instance of DbBtreeStat. The data -fields are available from DbBtreeStat: -<p><dl compact> -<p><dt>public int bt_magic;<dd>Magic number that identifies the file as a Btree database. -<dt>public int bt_version;<dd>The version of the Btree database. -<dt>public int bt_nkeys;<dd>For the Btree Access Method, the number of unique keys in the database. -<p>For the Recno Access Method, the number of records in the database. -<dt>public int bt_ndata;<dd>For the Btree Access Method, the number of key/data pairs in the database. -<p>For the Recno Access Method, the number of records in the database. If -the database has been configured to not re-number records during -deletion, the number of records will only reflect undeleted records. -<dt>public int bt_pagesize;<dd>Underlying database page size. -<dt>public int bt_minkey;<dd>The minimum keys per page. -<dt>public int bt_re_len;<dd>The length of fixed-length records. -<dt>public int bt_re_pad;<dd>The padding byte value for fixed-length records. -<dt>public int bt_levels;<dd>Number of levels in the database. -<dt>public int bt_int_pg;<dd>Number of database internal pages. -<dt>public int bt_leaf_pg;<dd>Number of database leaf pages. -<dt>public int bt_dup_pg;<dd>Number of database duplicate pages. -<dt>public int bt_over_pg;<dd>Number of database overflow pages. -<dt>public int bt_free;<dd>Number of pages on the free list. -<dt>public int bt_int_pgfree;<dd>Number of bytes free in database internal pages. -<dt>public int bt_leaf_pgfree;<dd>Number of bytes free in database leaf pages. -<dt>public int bt_dup_pgfree;<dd>Number of bytes free in database duplicate pages. -<dt>public int bt_over_pgfree;<dd>Number of bytes free in database overflow pages. -</dl> -<h3>Queue Statistics</h3> -<p>In the case of a Queue database, -the statistics are returned in an instance of DbQueueStat. The data -fields are available from DbQueueStat: -<p><dl compact> -<p><dt>public int qs_magic;<dd>Magic number that identifies the file as a Queue file. -<dt>public int qs_version;<dd>The version of the Queue file type. -<dt>public int qs_nkeys;<dd>The number of records in the database. -<dt>public int qs_ndata;<dd>The number of records in the database. -<dt>public int qs_pagesize;<dd>Underlying database page size. -<dt>public int qs_pages;<dd>Number of pages in the database. -<dt>public int qs_re_len;<dd>The length of the records. -<dt>public int qs_re_pad;<dd>The padding byte value for the records. -<dt>public int qs_pgfree;<dd>Number of bytes free in database pages. -<dt>public int qs_start;<dd>Start offset. -<dt>public int qs_first_recno;<dd>First undeleted record in the database. -<dt>public int qs_cur_recno;<dd>Last allocated record number in the database. -</dl> -<p>The Db.stat method throws an exception that encapsulates a non-zero error value on -failure. -<h1>Errors</h1> -<p>The Db.stat method may fail and throw an exception for errors specified for other Berkeley DB and C library or system methods. -If a catastrophic error has occurred, the Db.stat method may fail and throw -a <a href="../api_java/runrec_class.html">DbRunRecoveryException</a>, in which case all subsequent Berkeley DB calls -will fail in the same way. -<h3>Class</h3> -<a href="../api_java/db_class.html">Db</a> -<h1>See Also</h1> -<a href="../api_java/db_close.html">Db.close</a>, -<a href="../api_java/db_cursor.html">Db.cursor</a>, -<a href="../api_java/db_del.html">Db.del</a>, -<a href="../api_java/db_fd.html">Db.fd</a>, -<a href="../api_java/db_get.html">Db.get</a>, -<a href="../api_java/db_get_byteswapped.html">Db.get_byteswapped</a>, -<a href="../api_java/db_get_type.html">Db.get_type</a>, -<a href="../api_java/db_join.html">Db.join</a>, -<a href="../api_java/db_key_range.html">Db.key_range</a>, -<a href="../api_java/db_open.html">Db.open</a>, -<a href="../api_java/db_put.html">Db.put</a>, -<a href="../api_java/db_remove.html">Db.remove</a>, -<a href="../api_java/db_set_bt_minkey.html">Db.set_bt_minkey</a>, -<a href="../api_java/db_set_cachesize.html">Db.set_cachesize</a>, -<a href="../api_java/db_set_errcall.html">Db.set_errcall</a>, -<a href="../api_java/db_set_errpfx.html">Db.set_errpfx</a>, -<a href="../api_java/db_set_flags.html">Db.set_flags</a>, -<a href="../api_java/db_set_h_ffactor.html">Db.set_h_ffactor</a>, -<a href="../api_java/db_set_h_nelem.html">Db.set_h_nelem</a>, -<a href="../api_java/db_set_lorder.html">Db.set_lorder</a>, -<a href="../api_java/db_set_pagesize.html">Db.set_pagesize</a>, -<a href="../api_java/db_set_q_extentsize.html">Db.set_q_extentsize</a>, -<a href="../api_java/db_set_re_delim.html">Db.set_re_delim</a>, -<a href="../api_java/db_set_re_len.html">Db.set_re_len</a>, -<a href="../api_java/db_set_re_pad.html">Db.set_re_pad</a>, -<a href="../api_java/db_set_re_source.html">Db.set_re_source</a>, -<a href="../api_java/db_stat.html">Db.stat</a>, -<a href="../api_java/db_sync.html">Db.sync</a>, -<a href="../api_java/db_upgrade.html">Db.upgrade</a> -and -<a href="../api_java/db_verify.html">Db.verify</a>. -</tt> -<table><tr><td><br></td><td width="1%"> -<a href="../api_java/java_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> |