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<title>Berkeley DB: Db.set_pagesize</title>
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<h1>Db.set_pagesize</h1>
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<h3><pre>
import com.sleepycat.db.*;
<p>
public void set_pagesize(long pagesize)
    throws DbException;
</pre></h3>
<h1>Description</h1>
<p>Set the size of the pages used to hold items in the database, in bytes.
The minimum page size is 512 bytes, and the maximum page size is 64K
bytes.  If the page size is not explicitly set, one is selected based
on the underlying filesystem I/O block size.  The automatically selected
size has a lower limit of 512 bytes and an upper limit of 16K bytes.
<p>For information on tuning the Berkeley DB page size, see
<a href="../ref/am_conf/pagesize.html">Selecting a page size</a>.
<p>The Db.set_pagesize method configures a database, not only operations performed
using the specified <a href="../api_java/db_class.html">Db</a> handle.
<p>The Db.set_pagesize interface may not be called after the <a href="../api_java/db_open.html">Db.open</a>
interface is called.
If the database already exists when
<a href="../api_java/db_open.html">Db.open</a> is called, the information specified to Db.set_pagesize will
be ignored.
If creating additional databases in a file, the page size specified must
be consistent with the existing databases in the file or an error will
be returned.
<p>The Db.set_pagesize method throws an exception that encapsulates a non-zero error value on
failure.
<h1>Errors</h1>
<p>The Db.set_pagesize method may fail and throw an exception encapsulating a non-zero error for the following conditions:
<p><dl compact>
<p><dt>EINVAL<dd>An invalid flag value or parameter was specified.
<p>Called after <a href="../api_java/db_open.html">Db.open</a> was called.
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<p>The Db.set_pagesize 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.set_pagesize 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.
<h1>Class</h1>
<a href="../api_java/db_class.html">Db</a>
<h1>See Also</h1>
<a href="../api_java/db_list.html">Databases and Related Methods</a>
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