I have performed and extensive search of this site and yet to find a viable example of using clob. So here is one that works for me.
$the_blob=$htmlbody;
$db = OCILogon("randalls","dofa7h");
$clob = OCINewDescriptor($db, OCI_D_LO😎;
$stmt = OCIParse($db,"insert into web_content
(wc_id, wc_owner_id, wc_link, wc_date, wc_title, wc_category_id, the_blob) values
(web_content_seq.nextval, $ownerid, '$weblink',
SYSDATE,'$title',$category,
EMPTY_CLOB()) returning the_blob into :the_blob");
OCIBindByName($stmt,':the_blob', &$clob, -1, OCI_B_CLO😎;
OCIExecute($stmt, OCI_DEFAULT);
if($clob->save($htmlbody)){
OCICommit($db);
}else{
echo "Problems: Couldn't upload Clob\n";
}