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<h1>DB->del</h1>
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<h3><pre>
#include <db.h>
<p>
int
DB->del(DB *db, DB_TXN *txnid, DBT *key, u_int32_t flags);
</pre></h3>
<h1>Description</h1>
<p>The DB->del method removes key/data pairs from the database. The
key/data pair associated with the specified <b>key</b> is discarded from
the database. In the presence of duplicate key values, all records
associated with the designated key will be discarded.
<p>When called on a database that has been made into a secondary index
using the <a href="../api_c/db_associate.html">DB->associate</a> method, the DB->del method deletes the
key/data pair from the primary database and all secondary indices.
<p>If the operation is to be transaction-protected (other than by specifying
the DB_AUTO_COMMIT flag), the <b>txnid</b> parameter is a
transaction handle returned from <a href="../api_c/txn_begin.html">DB_ENV->txn_begin</a>; otherwise, NULL.
<p>The <b>flags</b> value must be set to 0 or
the following value:
<p><dl compact>
<p><dt><a name="DB_AUTO_COMMIT">DB_AUTO_COMMIT</a><dd>Enclose the DB->del call within a transaction. If the call succeeds,
changes made by the operation will be recoverable. If the call fails,
the operation will have made no changes.
</dl>
<p>
If the specified key is not in the database, the DB->del method will return DB_NOTFOUND.
Otherwise, the DB->del method returns a non-zero error value on failure and 0 on success.
<h1>Errors</h1>
<p>The DB->del method may fail and return a non-zero error for the following conditions:
<p><dl compact>
<p><dt>DB_LOCK_DEADLOCK<dd>The operation was selected to resolve a deadlock.
</dl>
<p><dl compact>
<p><dt>DB_SECONDARY_BAD<dd>A secondary index references a nonexistent primary key.
</dl>
<p><dl compact>
<p><dt>EACCES<dd>An attempt was made to modify a read-only database.
</dl>
<p><dl compact>
<p><dt>EINVAL<dd>An invalid flag value or parameter was specified.
</dl>
<p>The DB->del method may fail and return a non-zero error for errors specified for other Berkeley DB and C library or system functions.
If a catastrophic error has occurred, the DB->del method may fail and
return <a href="../ref/program/errorret.html#DB_RUNRECOVERY">DB_RUNRECOVERY</a>,
in which case all subsequent Berkeley DB calls will fail in the same way.
<h1>Class</h1>
<a href="../api_c/db_class.html">DB</a>
<h1>See Also</h1>
<a href="../api_c/db_list.html">Databases and Related Methods</a>
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