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<div class="sect1" lang="en" xml:lang="en">
<div class="titlepage">
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<div>
<h2 class="title" style="clear: both"><a id="dbcget"></a>Dbc::get()</h2>
</div>
</div>
</div>
<pre class="programlisting">#include <db_cxx.h>
int
Dbc::get(Dbt *key, Dbt *data, u_int32_t flags);
int
Dbc::pget(Dbt *key, Dbt *pkey, Dbt *data, u_int32_t flags); </pre>
<p>
The <code class="methodname">Dbc::get()</code> method retrieves key/data pairs from the
database. The address and length of the key are returned in the
object to which <span class="bold"><strong>key</strong></span> refers (except
for the case of the DB_SET flag, in which the <span class="bold"><strong>key</strong></span> object is unchanged), and the address and
length of the data are returned in the object to which <span class="bold"><strong>data</strong></span> refers.
</p>
<p>
When called on a cursor opened on a database that has been made into a
secondary index using the
<a class="xref" href="dbassociate.html" title="Db::associate()">Db::associate()</a> method, the
<code class="methodname">Dbc::get()</code> and <code class="methodname">Dbc::pget()</code>
methods return the key from the
secondary index and the data item from the primary database. In
addition, the <code class="methodname">Dbc::pget()</code> method returns the key from the
primary database. In databases that are not secondary indices, the
<code class="methodname">Dbc::pget()</code> method will always fail.
</p>
<p>
Modifications to the database during a sequential scan will be
reflected in the scan; that is, records inserted behind a cursor will
not be returned while records inserted in front of a cursor will be
returned.
</p>
<p>
In Queue and Recno databases, missing entries (that is, entries that
were never explicitly created or that were created and then deleted)
will be skipped during a sequential scan.
</p>
<p>
Unless otherwise specified, the <code class="methodname">Dbc::get()</code> <span>
<span>
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.
</span>
</span>
</p>
<p>
If <code class="methodname">Dbc::get()</code> fails for any reason, the state of the cursor will
be unchanged.
</p>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="id1656122"></a>Parameters</h3>
</div>
</div>
</div>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="id1656349"></a>data</h4>
</div>
</div>
</div>
<p>
The data <a class="link" href="dbt.html" title="Chapter 4. The Dbt Handle">Dbt</a> operated on.
</p>
</div>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="id1656522"></a>flags</h4>
</div>
</div>
</div>
<p>
The <span class="bold"><strong>flags</strong></span> parameter must be set to
one of the following values:
</p>
<div class="itemizedlist">
<ul type="disc">
<li>
<p><a id="dbcget_DB_CURRENT"></a>
<code class="literal">DB_CURRENT</code>
</p>
<p>
Return the key/data pair to which the cursor refers.
</p>
<p>
The <code class="methodname">Dbc::get()</code> method will return <a href="../../programmer_reference/program_errorret.html#program_errorret.DB_KEYEMPTY" class="olink">DB_KEYEMPTY</a> if
DB_CURRENT is set and the cursor key/data pair was deleted.
</p>
</li>
<li>
<p><a id="dbcget_DB_FIRST"></a>
<code class="literal">DB_FIRST</code>
</p>
<p>
The cursor is set to refer to the first key/data pair of the database,
and that pair is returned. If the first key has duplicate values, the
first data item in the set of duplicates is returned.
</p>
<p>
If the database is a Queue or Recno database, <code class="methodname">Dbc::get()</code> using
the DB_FIRST flag will ignore any keys that exist but were never
explicitly created by the application, or were created and later
deleted.
</p>
<p>
The <code class="methodname">Dbc::get()</code> method will return <a href="../../programmer_reference/program_errorret.html#program_errorret.DB_NOTFOUND" class="olink">DB_NOTFOUND</a> if
DB_FIRST is set and the database is empty.
</p>
</li>
<li>
<p><a id="dbcget_DB_GET_BOTH"></a>
<code class="literal">DB_GET_BOTH</code>
</p>
<p>
Move the cursor to the specified key/data pair of the
database. The cursor is positioned to a key/data pair if
both the key and data match the values provided on the key
and data parameters.
</p>
<p>
In all other ways, this flag is identical to the
<a class="link" href="dbcget.html#dbcget_DB_SET">DB_SET</a>
flag.
</p>
<p>
When used with <code class="methodname">Dbc::pget()</code> on
a secondary index handle, both the secondary and primary keys must be
matched by the secondary and primary key item in the database. It is
an error to use the DB_GET_BOTH flag with the <code class="methodname">Dbc::get()</code> version
of this method and a cursor that has been opened on a secondary index
handle.
</p>
</li>
<li>
<p><a id="dbcget_DB_GET_BOTH_RANGE"></a>
<code class="literal">DB_GET_BOTH_RANGE</code>
</p>
<p>
Move the cursor to the specified key/data pair of the
database. The key parameter must be an exact match with a
key in the database. The data item retrieved is the item in
a duplicate set that is the smallest value which is greater than or equal
to the value provided by the data parameter (as determined by the comparison
function). If this flag is specified on a database
configured without sorted duplicate support, the behavior
is identical to the DB_GET_BOTH flag. Returns the datum
associated with the given key/data pair.
</p>
<p>
In all other ways, this flag is identical to the
<a class="link" href="dbcget.html#dbcget_DB_GET_BOTH">DB_GET_BOTH</a>
flag.
</p>
</li>
<li>
<p><a id="dbcget_DB_GET_RECNO"></a>
<code class="literal">DB_GET_RECNO</code>
</p>
<p>
Return the record number associated with the cursor. The record
number will be returned in <span class="bold"><strong>data</strong></span>, as
described in <a class="link" href="dbt.html" title="Chapter 4. The Dbt Handle">Dbt</a>. The
<span class="bold"><strong>key</strong></span> parameter is ignored.
</p>
<p>
For DB_GET_RECNO to be specified, the underlying database must be of
type Btree, and it must have been created with the
<a class="link" href="dbset_flags.html#dbset_flags_DB_RECNUM">DB_RECNUM</a> flag.
</p>
<p>
When called on a cursor opened on a database that has been made into a
secondary index, the <code class="methodname">Dbc::get()</code> and
<code class="methodname">Dbc::pget()</code> methods return the record
number of the primary database in <span class="bold"><strong>data</strong></span>.
In addition, the <code class="methodname">Dbc::pget()</code>
method returns the record number of the secondary index in <span class="bold"><strong>pkey</strong></span>. If either underlying database is not of
type Btree or is not created with the
<a class="link" href="dbset_flags.html#dbset_flags_DB_RECNUM">DB_RECNUM</a>
flag, the out-of-band record number of 0 is returned.
</p>
</li>
<li>
<p><a id="dbcget_DB_JOIN_ITEM"></a>
<code class="literal">DB_JOIN_ITEM</code>
</p>
<p>
Do not use the data value found in all of the cursors as a lookup key
for the primary database, but simply return it in the key parameter
instead. The data parameter is left unchanged.
</p>
<p>
For DB_JOIN_ITEM to be specified, the underlying cursor must have been
returned from the <a class="xref" href="dbjoin.html" title="Db::join()">Db::join()</a> method.
</p>
</li>
<li>
<p><a id="dbcget_DB_LAST"></a>
<code class="literal">DB_LAST</code>
</p>
<p>
The cursor is set to refer to the last key/data pair of the database,
and that pair is returned. If the last key has duplicate values, the
last data item in the set of duplicates is returned.
</p>
<p>
If the database is a Queue or Recno database, <code class="methodname">Dbc::get()</code> using
the DB_LAST flag will ignore any keys that exist but were never
explicitly created by the application, or were created and later
deleted.
</p>
<p>
The <code class="methodname">Dbc::get()</code> method will return <a href="../../programmer_reference/program_errorret.html#program_errorret.DB_NOTFOUND" class="olink">DB_NOTFOUND</a> if
DB_LAST is set and the database is empty.
</p>
</li>
<li>
<p><a id="dbcget_DB_NEXT"></a>
<code class="literal">DB_NEXT</code>
</p>
<p>
If the cursor is not yet initialized, DB_NEXT is identical to
DB_FIRST. Otherwise, the cursor is moved to the next key/data pair of
the database, and that pair is returned. In the presence of duplicate
key values, the value of the key may not change.
</p>
<p>
If the database is a Queue or Recno database, <code class="methodname">Dbc::get()</code> using
the DB_NEXT flag will skip any keys that exist but were never
explicitly created by the application, or those that were created and
later deleted.
</p>
<p>
The <code class="methodname">Dbc::get()</code> method will return <a href="../../programmer_reference/program_errorret.html#program_errorret.DB_NOTFOUND" class="olink">DB_NOTFOUND</a> if
DB_NEXT is set and the cursor is already on the last record in the
database.
</p>
</li>
<li>
<p><a id="dbcget_DB_NEXT_DUP"></a>
<code class="literal">DB_NEXT_DUP</code>
</p>
<p>
If the next key/data pair of the database is a duplicate data record
for the current key/data pair, the cursor is moved to the next
key/data pair of the database, and that pair is returned.
</p>
<p>
The <code class="methodname">Dbc::get()</code> method will return <a href="../../programmer_reference/program_errorret.html#program_errorret.DB_NOTFOUND" class="olink">DB_NOTFOUND</a> if
DB_NEXT_DUP is set and the next key/data pair of the database is not a
duplicate data record for the current key/data pair.
</p>
</li>
<li>
<p><a id="dbcget_DB_NEXT_NODUP"></a>
<code class="literal">DB_NEXT_NODUP</code>
</p>
<p>
If the cursor is not yet initialized, DB_NEXT_NODUP is identical to
DB_FIRST. Otherwise, the cursor is moved to the next non-duplicate
key of the database, and that key/data pair is returned.
</p>
<p>
If the database is a Queue or Recno database, <code class="methodname">Dbc::get()</code> using
the DB_NEXT_NODUP flag will ignore any keys that exist but were never
explicitly created by the application, or those that were created and
later deleted.
</p>
<p>
The <code class="methodname">Dbc::get()</code> method will return <a href="../../programmer_reference/program_errorret.html#program_errorret.DB_NOTFOUND" class="olink">DB_NOTFOUND</a> if
DB_NEXT_NODUP is set and no non-duplicate key/data pairs exist after
the cursor position in the database.
</p>
</li>
<li>
<p><a id="dbcget_DB_PREV"></a>
<code class="literal">DB_PREV</code>
</p>
<p>
If the cursor is not yet initialized, DB_PREV is identical to DB_LAST.
Otherwise, the cursor is moved to the previous key/data pair of the
database, and that pair is returned. In the presence of duplicate key
values, the value of the key may not change.
</p>
<p>
If the database is a Queue or Recno database, <code class="methodname">Dbc::get()</code> using
the DB_PREV flag will skip any keys that exist but were never
explicitly created by the application, or those that were created and
later deleted.
</p>
<p>
The <code class="methodname">Dbc::get()</code> method will return <a href="../../programmer_reference/program_errorret.html#program_errorret.DB_NOTFOUND" class="olink">DB_NOTFOUND</a> if
DB_PREV is set and the cursor is already on the first record in the
database.
</p>
</li>
<li>
<p><a id="dbcget_DB_PREV_DUP"></a>
<code class="literal">DB_PREV_DUP</code>
</p>
<p>
If the previous key/data pair of the database is a duplicate data
record for the current key/data pair, the cursor is moved to the
previous key/data pair of the database, and that pair is returned.
</p>
<p>
The <code class="methodname">Dbc::get()</code> method will return <a href="../../programmer_reference/program_errorret.html#program_errorret.DB_NOTFOUND" class="olink">DB_NOTFOUND</a> if
DB_PREV_DUP is set and the previous key/data pair of the database is
not a duplicate data record for the current key/data pair.
</p>
</li>
<li>
<p><a id="dbcget_DB_PREV_NODUP"></a>
<code class="literal">DB_PREV_NODUP</code>
</p>
<p>
If the cursor is not yet initialized, DB_PREV_NODUP is identical to
DB_LAST. Otherwise, the cursor is moved to the previous non-duplicate
key of the database, and that key/data pair is returned.
</p>
<p>
If the database is a Queue or Recno database, <code class="methodname">Dbc::get()</code> using
the DB_PREV_NODUP flag will ignore any keys that exist but were never
explicitly created by the application, or those that were created and
later deleted.
</p>
<p>
The <code class="methodname">Dbc::get()</code> method will return <a href="../../programmer_reference/program_errorret.html#program_errorret.DB_NOTFOUND" class="olink">DB_NOTFOUND</a> if
DB_PREV_NODUP is set and no non-duplicate key/data pairs exist before
the cursor position in the database.
</p>
</li>
<li>
<p><a id="dbcget_DB_SET"></a>
<code class="literal">DB_SET</code>
</p>
<p>
Move the cursor to the specified key/data pair of the database, and
return the datum associated with the given key.
</p>
<p>
The <code class="methodname">Dbc::get()</code> method will return <a href="../../programmer_reference/program_errorret.html#program_errorret.DB_NOTFOUND" class="olink">DB_NOTFOUND</a> if
DB_SET is set and no matching keys are found. The
<code class="methodname">Dbc::get()</code> method will return <a href="../../programmer_reference/program_errorret.html#program_errorret.DB_KEYEMPTY" class="olink">DB_KEYEMPTY</a> if
DB_SET is set and the database is a Queue or Recno database, and the
specified key exists, but was never explicitly created by the
application or was later deleted. In the presence of duplicate key
values, <code class="methodname">Dbc::get()</code> will return the first data item for the given
key.
</p>
</li>
<li>
<p><a id="dbcget_DB_SET_RANGE"></a>
<code class="literal">DB_SET_RANGE</code>
</p>
<p>
Move the cursor to the specified key/data pair of the
database. In the case of the Btree access method, the key
is returned as well as the data item and the returned
key/data pair is the smallest key greater than or equal to
the specified key (as determined by the Btree comparison
function), permitting partial key matches and range
searches.
</p>
<p>
In all other ways the behavior of this flag is the same
as the <a class="link" href="dbcget.html#dbcget_DB_SET">DB_SET</a> flag.
</p>
</li>
<li>
<p><a id="dbcget_DB_SET_RECNO"></a>
<code class="literal">DB_SET_RECNO</code>
</p>
<p>
Move the cursor to the specific numbered record of the database, and
return the associated key/data pair. The <span class="bold"><strong>data</strong></span> field of the specified <span class="bold"><strong>key</strong></span> must be a pointer to a memory location from
which a <code class="literal">db_recno_t</code> may be
read, as described in <a class="link" href="dbt.html" title="Chapter 4. The Dbt Handle">Dbt</a>. This memory location will
be read to determine the record to be retrieved.
</p>
<p>
For DB_SET_RECNO to be specified, the underlying database must be of
type Btree, and it must have been created with the
<a class="link" href="dbset_flags.html#dbset_flags_DB_RECNUM">DB_RECNUM</a> flag.
</p>
</li>
</ul>
</div>
<p>
In addition, the following flags may be set by bitwise inclusively
<span class="bold"><strong>OR</strong></span>'ing them into the <span class="bold"><strong>flags</strong></span> parameter:
</p>
<div class="itemizedlist">
<ul type="disc">
<li>
<p>
<code class="literal">DB_IGNORE_LEASE</code>
</p>
<p>
This flag is relevant only when using a replicated
environment.
</p>
<p>
Return the data item irrespective of the state of master leases. The
item will be returned under all conditions: if master leases are not
configured, if the request is made to a client, if the request is made
to a master with a valid lease, or if the request is made to a master
without a valid lease.
</p>
</li>
<li>
<p><a id="dbcget_DB_READ_COMMITTED"></a>
<code class="literal">DB_READ_COMMITTED</code>
</p>
<p>
Configure a transactional get operation to have degree 2 isolation
(the read is not repeatable).
</p>
</li>
<li>
<p>
<code class="literal">DB_READ_UNCOMMITTED</code>
</p>
<p>
Database items read during a transactional call will have degree 1
isolation, including modified but not yet committed data. Silently
ignored if the
<a class="link" href="dbopen.html#dbopen_DB_READ_UNCOMMITTED">DB_READ_UNCOMMITTED</a>
flag was not specified when the underlying database was opened.
</p>
</li>
<li>
<p><a id="dbcget_DB_MULTIPLE"></a>
<code class="literal">DB_MULTIPLE</code>
</p>
<p>
Return multiple data items in the <span class="bold"><strong>data</strong></span> parameter.
</p>
<p>
In the case of Btree or Hash databases, duplicate data items for the
current key, starting at the current cursor position, are entered into
the buffer. Subsequent calls with both the DB_NEXT_DUP and
DB_MULTIPLE flags specified will return additional duplicate data
items associated with the current key or <a href="../../programmer_reference/program_errorret.html#program_errorret.DB_NOTFOUND" class="olink">DB_NOTFOUND</a> if
there are no additional duplicate data items to return. Subsequent
calls with both the DB_NEXT and DB_MULTIPLE flags specified will
return additional duplicate data items associated with the current key
or if there are no additional duplicate data items will return the
next key and its data items or <a href="../../programmer_reference/program_errorret.html#program_errorret.DB_NOTFOUND" class="olink">DB_NOTFOUND</a> if
there are no additional keys in the database.
</p>
<p>
In the case of Queue or Recno databases, data items starting at the
current cursor position are entered into the buffer. The record
number of the first record will be returned in the <span class="bold"><strong>key</strong></span> parameter. The record number of each
subsequent returned record must be calculated from this value.
Subsequent calls with the DB_MULTIPLE flag specified will return
additional data items or <a href="../../programmer_reference/program_errorret.html#program_errorret.DB_NOTFOUND" class="olink">DB_NOTFOUND</a> if
there are no additional data items to return.
</p>
<p>
The buffer to which the <span class="bold"><strong>data</strong></span>
parameter refers must be provided from user memory (see
<a class="link" href="dbt.html#dbt_DB_DBT_USERMEM">DB_DBT_USERMEM</a> ).
The buffer must be at least as large as the page size of the
underlying database, aligned for unsigned integer access, and be a
multiple of 1024 bytes in size. If the buffer size is insufficient,
then upon return from the call the size field of the <span class="bold"><strong>data</strong></span> parameter will have been set to an
estimated buffer size, and the error DB_BUFFER_SMALL is returned.
(The size is an estimate as the exact size needed may not be known
until all entries are read. It is best to initially provide a
relatively large buffer, but applications should be prepared to resize
the buffer as necessary and repeatedly call the method.)
</p>
<p>
The multiple data items can be iterated over using the
<span>
<a class="xref" href="dbmultipledataiterator.html" title="DbMultipleDataIterator">DbMultipleDataIterator</a> class.
</span>
</p>
<p>
The DB_MULTIPLE flag may only be used with the DB_CURRENT, DB_FIRST,
DB_GET_BOTH, DB_GET_BOTH_RANGE, DB_NEXT, DB_NEXT_DUP, DB_NEXT_NODUP,
DB_SET, DB_SET_RANGE, and DB_SET_RECNO options. The DB_MULTIPLE flag
may not be used when accessing databases made into secondary indices
using the <a class="xref" href="dbassociate.html" title="Db::associate()">Db::associate()</a> method.
</p>
</li>
<li>
<p><a id="dbcget_DB_MULTIPLE_KEY"></a>
<code class="literal">DB_MULTIPLE_KEY</code>
</p>
<p>
Return multiple key and data pairs in the <span class="bold"><strong>data</strong></span> parameter.
</p>
<p>
Key and data pairs, starting at the current cursor position, are
entered into the buffer. Subsequent calls with both the DB_NEXT and
DB_MULTIPLE_KEY flags specified will return additional key and data
pairs or <a href="../../programmer_reference/program_errorret.html#program_errorret.DB_NOTFOUND" class="olink">DB_NOTFOUND</a> if
there are no additional key and data items to return.
</p>
<p>
In the case of Btree or Hash databases, the multiple key and data
pairs can be iterated over using the
<span>
<a class="xref" href="dbmultiplekeydataiterator.html" title="DbMultipleKeyDataIterator">DbMultipleKeyDataIterator</a> class.
</span>
</p>
<p>
In the case of Queue or Recno databases, the multiple record number
and data pairs can be iterated over using the
<span>
<a class="xref" href="dbmultiplerecnodataiterator.html" title="DbMultipleRecnoDataIterator">DbMultipleRecnoDataIterator</a> class.
</span>
</p>
<p>
The buffer to which the <span class="bold"><strong>data</strong></span>
parameter refers must be provided from user memory (see
<a class="link" href="dbt.html#dbt_DB_DBT_USERMEM">DB_DBT_USERMEM</a> ).
The buffer must be at least as large as the page size of the
underlying database, aligned for unsigned integer access, and be a
multiple of 1024 bytes in size. If the buffer size is insufficient,
then upon return from the call the size field of the <span class="bold"><strong>data</strong></span> parameter will have been set to an
estimated buffer size, and the error DB_BUFFER_SMALL is returned.
(The size is an estimate as the exact size needed may not be known
until all entries are read. It is best to initially provide a
relatively large buffer, but applications should be prepared to resize
the buffer as necessary and repeatedly call the method.)
</p>
<p>
The DB_MULTIPLE_KEY flag may only be used with the DB_CURRENT,
DB_FIRST, DB_GET_BOTH, DB_GET_BOTH_RANGE, DB_NEXT, DB_NEXT_DUP,
DB_NEXT_NODUP, DB_SET, DB_SET_RANGE, and DB_SET_RECNO options. The
DB_MULTIPLE_KEY flag may not be used when accessing databases made
into secondary indices using the
<a class="xref" href="dbassociate.html" title="Db::associate()">Db::associate()</a> method.
</p>
</li>
<li>
<p><a id="dbcget_DB_RMW"></a>
<code class="literal">DB_RMW</code>
</p>
<p>
Acquire write locks instead of read locks when doing the read, if
locking is configured. Setting this flag can eliminate deadlock
during a read-modify-write cycle by acquiring the write lock during
the read part of the cycle so that another thread of control acquiring
a read lock for the same item, in its own read-modify-write cycle,
will not result in deadlock.
</p>
</li>
</ul>
</div>
</div>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="id1656421"></a>key</h4>
</div>
</div>
</div>
<p>
The key <a class="link" href="dbt.html" title="Chapter 4. The Dbt Handle">Dbt</a> operated on.
</p>
</div>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="id1656800"></a>pkey</h4>
</div>
</div>
</div>
<p>
The secondary index key <a class="link" href="dbt.html" title="Chapter 4. The Dbt Handle">Dbt</a> operated on.
</p>
</div>
</div>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="id1656464"></a>Errors</h3>
</div>
</div>
</div>
<p>
The <code class="methodname">Dbc::get()</code> <span>
<span>
method may fail and throw a <a class="link" href="dbexception.html" title="Chapter 6. The DbException Class">DbException</a>
exception, encapsulating one of the following non-zero errors, or return one
of the following non-zero errors:
</span>
</span>
</p>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="id1656919"></a><span>DbMemoryException or </span>DB_BUFFER_SMALL</h4>
</div>
</div>
</div>
<p>
The requested item could not be returned due to undersized buffer.
</p>
<p>
<a class="xref" href="dbmemory.html" title="DbMemoryException">DbMemoryException</a> is thrown if
your Berkeley DB API is configured to throw exceptions.
Otherwise, <code class="literal">DB_BUFFER_SMALL</code> is returned.
</p>
</div>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="id1656904"></a><span>DbDeadlockException or </span>DB_LOCK_DEADLOCK</h4>
</div>
</div>
</div>
<p>
A transactional database environment operation was selected to resolve
a deadlock.
</p>
<p>
<a class="xref" href="dbdeadlock.html" title="DbDeadlockException">DbDeadlockException</a> is thrown if
your Berkeley DB API is configured to throw exceptions.
Otherwise, <code class="literal">DB_LOCK_DEADLOCK</code> is returned.
</p>
</div>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="id1656696"></a><span>DbLockNotGrantedException or </span>DB_LOCK_NOTGRANTED</h4>
</div>
</div>
</div>
<p>
A Berkeley DB Concurrent Data Store database environment configured
for lock timeouts was unable to grant a lock in the allowed time.
</p>
<p>
<a class="xref" href="dblocknotgranted.html" title="DbLockNotGrantedException">DbLockNotGrantedException</a> is thrown if
your Berkeley DB API is configured to throw exceptions.
Otherwise, <code class="literal">DB_LOCK_NOTGRANTED</code> is returned.
</p>
</div>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="id1657114"></a><span>DbRepHandleDeadException or</span> DB_REP_HANDLE_DEAD</h4>
</div>
</div>
</div>
<p>
When a client synchronizes with the master, it is possible for committed
transactions to be rolled back. This invalidates all the database and cursor
handles opened in the replication environment. Once this occurs, an attempt to use
such a handle will
<span>
throw a <a class="xref" href="dbrephandledead.html" title="DbRepHandleDeadException">DbRepHandleDeadException</a> (if
your application is configured to throw exceptions), or
</span>
return <code class="literal">DB_REP_HANDLE_DEAD</code>.
The application will need to discard the handle and open a new one in order to
continue processing.
</p>
</div>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="id1656730"></a>DB_REP_LEASE_EXPIRED</h4>
</div>
</div>
</div>
<p>
The operation failed because the site's replication master lease has expired.
</p>
</div>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="id1657782"></a><span>DbDeadlockException or </span>DB_REP_LOCKOUT</h4>
</div>
</div>
</div>
<p>
The operation was blocked by client/master synchronization.
</p>
<p>
<a class="xref" href="dbdeadlock.html" title="DbDeadlockException">DbDeadlockException</a> is thrown if
your Berkeley DB API is configured to throw exceptions.
Otherwise, <code class="literal">DB_REP_LOCKOUT</code> is returned.
</p>
</div>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="id1656913"></a>DB_SECONDARY_BAD</h4>
</div>
</div>
</div>
<p>
A secondary index references a nonexistent primary key.
</p>
</div>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="id1657865"></a>EINVAL</h4>
</div>
</div>
</div>
<p>
If the DB_CURRENT, DB_NEXT_DUP or DB_PREV_DUP flags were specified and
the cursor has not been initialized; the <code class="methodname">Dbc::pget()</code> method was
called with a cursor that does not refer to a secondary index; or if
an invalid flag value or parameter was specified.
</p>
</div>
</div>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="id1656455"></a>Class</h3>
</div>
</div>
</div>
<p>
<a class="link" href="dbc.html" title="Chapter 3. The Dbc Handle">Dbc</a>
</p>
</div>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="id1656418"></a>See Also</h3>
</div>
</div>
</div>
<p>
<a class="xref" href="dbc.html#dbclist" title="Database Cursors and Related Methods">Database Cursors and Related Methods</a>
</p>
</div>
</div>
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distrib
>
Mandriva
>
2010.1
>
x86_64
>
media
>
main-release
>
by-pkgid
>
a00abf5f94bf470fd4cc9e10b2d135e0
>
files
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416
