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<h1>DbEnv.txn_stat</h1>
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<h3><pre>
import com.sleepycat.db.*;
<p>
public DbTxnStat txn_stat()
	throws DbException;
</pre></h3>
<h1>Description</h1>
<p>The DbEnv.txn_stat method
creates a DbTxnStat object encapsulating a statistical structure.
The transaction region statistics are stored in a DbTxnStat object.
The following data fields are available from the DbTxnStat object:
<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 transaction region statistics are stored in a structure of type
DB_TXN_STAT.  The following DB_TXN_STAT fields will be filled in:
<p><dl compact>
<dt>public <a href="../api_java/lsn_class.html">DbLsn</a> st_last_ckp;<dd>The LSN of the last checkpoint.
<dt>public <a href="../api_java/lsn_class.html">DbLsn</a> st_pending_ckp;<dd>The LSN of any checkpoint that is currently in progress.  If
<b>st_pending_ckp</b> is the same as <b>st_last_ckp</b> there
is no checkpoint in progress.
<dt>public long st_time_ckp;<dd>The time the last completed checkpoint finished (as the number of seconds
since the Epoch, returned by the IEEE/ANSI Std 1003.1 (POSIX) <b>time</b> interface).
<dt>public int st_last_txnid;<dd>The last transaction ID allocated.
<dt>public int st_maxtxns;<dd>The maximum number of active transactions possible.
<dt>public int st_nactive;<dd>The number of transactions that are currently active.
<dt>public int st_maxnactive;<dd>The maximum number of active transactions at any one time.
<dt>public int st_nbegins;<dd>The number of transactions that have begun.
<dt>public int st_naborts;<dd>The number of transactions that have aborted.
<dt>public int st_ncommits;<dd>The number of transactions that have committed.
<dt>public int st_regsize;<dd>The size of the region.
<dt>public int st_region_wait;<dd>The number of times that a thread of control was forced to wait before
obtaining the region lock.
<dt>public int st_region_nowait;<dd>The number of times that a thread of control was able to obtain
the region lock without waiting.
<dt>public Active st_txnarray[];<dd>The array of active transactions.  Each element of the array is an object
of type DbTxnStat.Active, a top level inner class, that has the following
fields:
<p><dl compact>
<p><dt>public int txnid;<dd>The Transaction ID.
<dt>public DbLsn lsn;<dd>The Lsn of the begin record.
</dl>
</dl>
<p>The DbEnv.txn_stat method throws an exception that encapsulates a non-zero error value on
failure.
<h1>Errors</h1>
<p>The DbEnv.txn_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 DbEnv.txn_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>Classes</h3>
<a href="../api_java/dbenv_class.html">DbEnv</a>, <a href="../api_java/txn_class.html">DbTxn</a>
<h1>See Also</h1>
<a href="../api_java/env_set_tx_max.html">DbEnv.set_tx_max</a>,
<a href="../api_java/env_set_tx_timestamp.html">DbEnv.set_tx_timestamp</a>,
<a href="../api_java/txn_abort.html">DbTxn.abort</a>,
<a href="../api_java/txn_begin.html">DbEnv.txn_begin</a>,
<a href="../api_java/txn_checkpoint.html">DbEnv.txn_checkpoint</a>,
<a href="../api_java/txn_commit.html">DbTxn.commit</a>,
<a href="../api_java/txn_id.html">DbTxn.id</a>,
<a href="../api_java/txn_prepare.html">DbTxn.prepare</a>
and
<a href="../api_java/txn_stat.html">DbEnv.txn_stat</a>.
</tt>
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