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<h1>DB-&gt;del</h1>
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<h3><pre>
#include &lt;db.h&gt;
<p>
int
DB-&gt;del(DB *db, DB_TXN *txnid, DBT *key, u_int32_t flags);
</pre></h3>
<h1>Description</h1>
<p>The DB-&gt;del function 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>If the file is being accessed under transaction protection, the
<b>txnid</b> parameter is a transaction ID returned from
<a href="../api_c/txn_begin.html">txn_begin</a>, otherwise, NULL.
<p>The <b>flags</b> parameter is currently unused, and must be set to 0.
<p>The DB-&gt;del function returns a non-zero error value on failure, 0 on success, and <a href="../ref/program/errorret.html#DB_NOTFOUND">DB_NOTFOUND</a> if the specified <b>key</b> did not exist in
the file.
<h1>Errors</h1>
<p>The DB-&gt;del function 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>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-&gt;del function 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-&gt;del function 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>See Also</h1>
<a href="../api_c/db_create.html">db_create</a>,
<a href="../api_c/db_close.html">DB-&gt;close</a>,
<a href="../api_c/db_cursor.html">DB-&gt;cursor</a>,
<a href="../api_c/db_del.html">DB-&gt;del</a>,
<a href="../api_c/db_err.html">DB-&gt;err</a>,
<a href="../api_c/db_fd.html">DB-&gt;fd</a>,
<a href="../api_c/db_get.html">DB-&gt;get</a>,
<a href="../api_c/db_get_byteswapped.html">DB-&gt;get_byteswapped</a>,
<a href="../api_c/db_get_type.html">DB-&gt;get_type</a>,
<a href="../api_c/db_join.html">DB-&gt;join</a>,
<a href="../api_c/db_key_range.html">DB-&gt;key_range</a>,
<a href="../api_c/db_open.html">DB-&gt;open</a>,
<a href="../api_c/db_put.html">DB-&gt;put</a>,
<a href="../api_c/db_remove.html">DB-&gt;remove</a>,
<a href="../api_c/db_set_bt_compare.html">DB-&gt;set_bt_compare</a>,
<a href="../api_c/db_set_bt_minkey.html">DB-&gt;set_bt_minkey</a>,
<a href="../api_c/db_set_bt_prefix.html">DB-&gt;set_bt_prefix</a>,
<a href="../api_c/db_set_cachesize.html">DB-&gt;set_cachesize</a>,
<a href="../api_c/db_set_dup_compare.html">DB-&gt;set_dup_compare</a>,
<a href="../api_c/db_set_errcall.html">DB-&gt;set_errcall</a>,
<a href="../api_c/db_set_errfile.html">DB-&gt;set_errfile</a>,
<a href="../api_c/db_set_errpfx.html">DB-&gt;set_errpfx</a>,
<a href="../api_c/db_set_flags.html">DB-&gt;set_flags</a>,
<a href="../api_c/db_set_h_ffactor.html">DB-&gt;set_h_ffactor</a>,
<a href="../api_c/db_set_h_hash.html">DB-&gt;set_h_hash</a>,
<a href="../api_c/db_set_h_nelem.html">DB-&gt;set_h_nelem</a>,
<a href="../api_c/db_set_lorder.html">DB-&gt;set_lorder</a>,
<a href="../api_c/db_set_malloc.html">DB-&gt;set_malloc</a>,
<a href="../api_c/db_set_pagesize.html">DB-&gt;set_pagesize</a>,
<a href="../api_c/db_set_paniccall.html">DB-&gt;set_paniccall</a>,
<a href="../api_c/db_set_q_extentsize.html">DB-&gt;set_q_extentsize</a>,
<a href="../api_c/db_set_realloc.html">DB-&gt;set_realloc</a>,
<a href="../api_c/db_set_re_delim.html">DB-&gt;set_re_delim</a>,
<a href="../api_c/db_set_re_len.html">DB-&gt;set_re_len</a>,
<a href="../api_c/db_set_re_pad.html">DB-&gt;set_re_pad</a>,
<a href="../api_c/db_set_re_source.html">DB-&gt;set_re_source</a>,
<a href="../api_c/db_stat.html">DB-&gt;stat</a>,
<a href="../api_c/db_sync.html">DB-&gt;sync</a>,
<a href="../api_c/db_upgrade.html">DB-&gt;upgrade</a>
and
<a href="../api_c/db_verify.html">DB-&gt;verify</a>.
</tt>
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