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<div class="sect1" lang="en" xml:lang="en">
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<h2 class="title" style="clear: both"><a id="dbput"></a>DB->put()</h2>
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<pre class="programlisting">#include <db.h>
int
DB->put(DB *db,
DB_TXN *txnid, DBT *key, DBT *data, u_int32_t flags); </pre>
<p>
The <code class="methodname">DB->put()</code> method stores key/data pairs in the database. The
default behavior of the <code class="methodname">DB->put()</code> function is to enter the new
key/data pair, replacing any previously existing key if duplicates are
disallowed, or adding a duplicate data item if duplicates are allowed.
If the database supports duplicates, the <code class="methodname">DB->put()</code> method adds the
new data value at the end of the duplicate set. If the database
supports sorted duplicates, the new data value is inserted at the
correct sorted location.
</p>
<p>
Unless otherwise specified, the <code class="methodname">DB->put()</code> <span>
<span>
method returns a non-zero error value on failure and 0 on success.
</span>
</span>
</p>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="id1640762"></a>Parameters</h3>
</div>
</div>
</div>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="id1640789"></a>flags</h4>
</div>
</div>
</div>
<p>
The <span class="bold"><strong>flags</strong></span> parameter must be set to 0
or one of the following values:
</p>
<div class="itemizedlist">
<ul type="disc">
<li>
<p><a id="dbput_DB_APPEND"></a>
<code class="literal">DB_APPEND</code>
</p>
<p>
Append the key/data pair to the end of the database. For the
DB_APPEND flag to be specified, the underlying database must be a
Queue or Recno database. The record number allocated to the record is
returned in the specified <span class="bold"><strong>key</strong></span>.
</p>
<p>
There is a minor behavioral difference between the Recno
and Queue access methods for the DB_APPEND flag. If a
transaction enclosing a
<code class="methodname">DB->put()</code> operation with the
DB_APPEND flag aborts, the record number may be
reallocated in a subsequent <code class="literal">DB_APPEND</code>
operation if you are using the Recno access method, but it
will not be reallocated if you are using the Queue access
method.
</p>
</li>
<li>
<p><a id="put_DB_NODUPDATA"></a>
<code class="literal">DB_NODUPDATA</code>
</p>
<p>
In the case of the Btree and Hash access methods, enter the new
key/data pair only if it does not already appear in the database.
</p>
<p>
The DB_NODUPDATA flag may only be specified if the underlying database
has been configured to support sorted duplicates. The DB_NODUPDATA
flag may not be specified to the Queue or Recno access methods.
</p>
<p>
The <code class="methodname">DB->put()</code> method will return
<a class="xref" href="dbcput.html#dbcput_DB_KEYEXIST" title="DB_KEYEXIST">DB_KEYEXIST</a>
if DB_NODUPDATA is set and the key/data pair already appears in the
database.
</p>
</li>
<li>
<p><a id="put_DB_NOOVERWRITE"></a>
<code class="literal">DB_NOOVERWRITE</code>
</p>
<p>
Enter the new key/data pair only if the key does not already appear in
the database. The <code class="methodname">DB->put()</code> method call with the DB_NOOVERWRITE flag
set will fail if the key already exists in the database, even if the
database supports duplicates.
</p>
<p>
The <code class="methodname">DB->put()</code> method will return
<a class="xref" href="dbcput.html#dbcput_DB_KEYEXIST" title="DB_KEYEXIST">DB_KEYEXIST</a>
if DB_NOOVERWRITE is set and the key already appears in the database.
</p>
<p>
This enforcement of uniqueness of keys applies only to the primary key. The
behavior of insertions into secondary databases is not affected by the
DB_NOOVERWRITE flag. In particular, the insertion of a record that would result in
the creation of a duplicate key in a secondary database that allows duplicates would
not be prevented by the use of this flag.
</p>
</li>
<li>
<p><a id="put_DB_MULTIPLE"></a>
<code class="literal">DB_MULTIPLE</code>
</p>
<p>
Put multiple data items using keys from the buffer to which the <span class="bold"><strong>key</strong></span> parameter refers and data values from the buffer to
which the <span class="bold"><strong>data</strong></span> parameter refers.
</p>
<p>
To put records in bulk with the btree or hash access methods, construct bulk buffers
in the <span class="bold"><strong>key</strong></span> and
<span class="bold"><strong>data</strong></span>
<a class="link" href="dbt.html" title="Chapter 4. The DBT Handle">DBT</a> using
<a class="xref" href="DB_MULTIPLE_WRITE_INIT.html" title="DB_MULTIPLE_WRITE_INIT">DB_MULTIPLE_WRITE_INIT</a> and
<a class="xref" href="DB_MULTIPLE_WRITE_NEXT.html" title="DB_MULTIPLE_WRITE_NEXT">DB_MULTIPLE_WRITE_NEXT</a>. To
put records in bulk with the recno or queue access methods, construct bulk buffers
in the <span class="bold"><strong>data</strong></span> <a class="link" href="dbt.html" title="Chapter 4. The DBT Handle">DBT</a>
as before, but construct the <span class="bold"><strong>key</strong></span>
<a class="link" href="dbt.html" title="Chapter 4. The DBT Handle">DBT</a> using
<a class="xref" href="DB_MULTIPLE_RECNO_WRITE_INIT.html" title="DB_MULTIPLE_RECNO_WRITE_INIT">DB_MULTIPLE_RECNO_WRITE_INIT</a>
and <a class="xref" href="DB_MULTIPLE_RECNO_WRITE_NEXT.html" title="DB_MULTIPLE_RECNO_WRITE_NEXT">DB_MULTIPLE_RECNO_WRITE_NEXT</a>
with a data size of zero.
</p>
<p>
A successful bulk operation is logically equivalent to a loop through each key/data
pair, performing a <a class="xref" href="dbput.html" title="DB->put()">DB->put()</a> for each one.
</p>
<p>
See <a class="xref" href="dbt.html#dbtlist" title="DBT and Bulk Operations">DBT and Bulk Operations</a> for more information on
working with bulk updates.
</p>
<p>
The <code class="literal">DB_MULTIPLE</code> flag may only be used alone, or with the
<code class="literal">DB_OVERWRITE_DUP</code> option.
</p>
</li>
<li>
<p><a id="put_DB_MULTIPLE_KEY"></a>
<code class="literal">DB_MULTIPLE_KEY</code>
</p>
<p>
Put multiple data items using keys and data from the buffer to which the
<span class="bold"><strong>key</strong></span> parameter refers.
</p>
<p>
To put records in bulk with the btree or hash access methods, construct a single
bulk buffer in the <span class="bold"><strong>key</strong></span>
<a class="link" href="dbt.html" title="Chapter 4. The DBT Handle">DBT</a> using
<a class="xref" href="DB_MULTIPLE_WRITE_INIT.html" title="DB_MULTIPLE_WRITE_INIT">DB_MULTIPLE_WRITE_INIT</a> and
<a class="xref" href="DB_MULTIPLE_KEY_WRITE_NEXT.html" title="DB_MULTIPLE_KEY_WRITE_NEXT">DB_MULTIPLE_KEY_WRITE_NEXT</a>.
To put records in bulk with the recno or queue access methods, construct a
bulk buffer in the <span class="bold"><strong>key</strong></span>
<a class="link" href="dbt.html" title="Chapter 4. The DBT Handle">DBT</a> using
<a class="xref" href="DB_MULTIPLE_RECNO_WRITE_INIT.html" title="DB_MULTIPLE_RECNO_WRITE_INIT">DB_MULTIPLE_RECNO_WRITE_INIT</a> and
<a class="xref" href="DB_MULTIPLE_RECNO_WRITE_NEXT.html" title="DB_MULTIPLE_RECNO_WRITE_NEXT">DB_MULTIPLE_RECNO_WRITE_NEXT</a>.
</p>
<p>
See <a class="xref" href="dbt.html#dbtlist" title="DBT and Bulk Operations">DBT and Bulk Operations</a> for more information on
working with bulk updates.
</p>
<p>
The <code class="literal">DB_MULTIPLE_KEY</code> flag may only be used alone, or with the
<code class="literal">DB_OVERWRITE_DUP</code> option.
</p>
</li>
<li>
<p><a id="put_DB_OVERWRITE_DUP"></a>
<code class="literal">DB_OVERWRITE_DUP</code>
</p>
<p>
Ignore duplicate records when overwriting records in a database configured for
sorted duplicates.
</p>
<p>
Normally, if a database is configured for sorted duplicates, an attempt to
put a record that compares identically to a record already existing in the
database will fail. Using this flag causes the put to silently proceed, without
failure.
</p>
<p>
This flag is extremely useful when performing bulk puts (using the
<code class="literal">DB_MULTIPLE</code> or <code class="literal">DB_MULTIPLE_KEY</code> flags).
Depending on the number of records you are writing to the database with a bulk
put, you may not want the operation to fail in the event that a
duplicate record is encountered. Using this flag along with the
<code class="literal">DB_MULTIPLE</code> or <code class="literal">DB_MULTIPLE_KEY</code> flags
allows the bulk put to complete, even if a duplicate record is encountered.
</p>
<p>
This flag is also useful if you are using a custom comparison function that compares only
part of the data portion of a record. In this case, two records can compare
equally when, in fact, they are not equal. This flag allows the put to
complete, even if your custom comparison routine claims the two records are
equal.
</p>
</li>
</ul>
</div>
</div>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="id1640950"></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="id1640928"></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="id1641093"></a>txnid</h4>
</div>
</div>
</div>
<p>
If the operation is part of an application-specified transaction, the
<span class="bold"><strong>txnid</strong></span> parameter is a transaction
handle returned from <a class="xref" href="txnbegin.html" title="DB_ENV->txn_begin()">DB_ENV->txn_begin()</a>; if the
operation is part of a Berkeley DB Concurrent Data Store group, the
<span class="bold"><strong>txnid</strong></span> parameter is a handle returned
from <a class="xref" href="envcdsgroup_begin.html" title="DB_ENV->cdsgroup_begin()">DB_ENV->cdsgroup_begin()</a>;
otherwise NULL. If no transaction handle is specified, but the
operation occurs in a transactional database, the operation will be
implicitly transaction protected.
</p>
</div>
</div>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="id1640780"></a>Errors</h3>
</div>
</div>
</div>
<p>
The <code class="methodname">DB->put()</code> <span>
<span>
method may fail and 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="id1641421"></a>DB_FOREIGN_CONFLICT</h4>
</div>
</div>
</div>
<p>
A <a class="link" href="dbassociate_foreign.html" title="DB->associate_foreign()">foreign key constraint violation</a>
has occurred. This can be caused by one of two things:
</p>
<div class="orderedlist">
<ol type="1">
<li>
<p>
An attempt was made to add a record to a
constrained database, and the key used for that
record does not exist in the foreign key
database.
</p>
</li>
<li>
<p>
<a class="link" href="dbassociate_foreign.html#associate_foreign_DB_FOREIGN_ABORT">DB_FOREIGN_ABORT</a>
was declared for a foreign key database, and then
subsequently a record was deleted from the
foreign key database without first removing it
from the constrained secondary database.
</p>
</li>
</ol>
</div>
</div>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="id1640976"></a>DB_LOCK_DEADLOCK</h4>
</div>
</div>
</div>
<p>
A transactional database environment operation was selected to resolve
a deadlock.
</p>
</div>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="id1641388"></a>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>
</div>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="id1641175"></a> 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
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>
<a id="dbput_DB_REP_LOCKOUT"></a>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="id1641519"></a>DB_REP_LOCKOUT</h4>
</div>
</div>
</div>
<p>
The operation was blocked by client/master synchronization.
</p>
</div>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="id1641476"></a>EACCES</h4>
</div>
</div>
</div>
<p>
An attempt was made to modify a read-only database.
</p>
</div>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="id1641170"></a>EINVAL</h4>
</div>
</div>
</div>
<p>
If a record number of 0 was specified; an attempt was made to add a
record to a fixed-length database that was too large to fit; an
attempt was made to do a partial put; an attempt was made to add a
record to a secondary index; or if an invalid flag value or parameter
was specified.
</p>
</div>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="id1640802"></a>ENOSPC</h4>
</div>
</div>
</div>
<p>
A btree exceeded the maximum btree depth (255).
</p>
</div>
</div>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="id1640822"></a>Class</h3>
</div>
</div>
</div>
<p>
<a class="link" href="db.html" title="Chapter 2. The DB Handle">DB</a>
</p>
</div>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="id1640884"></a>See Also</h3>
</div>
</div>
</div>
<p>
<a class="xref" href="db.html#dblist" title="Database and Related Methods">Database and Related Methods</a>
</p>
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