where_link($t,$c,$Y,$Yd="="){return"&where%5B$t%5D%5Bcol%5D=".urlencode($c)."&where%5B$t%5D%5Bop%5D=".urlencode(($Y!==null?$Yd:"IS NULL"))."&where%5B$t%5D%5Bval%5D=".urlencode($Y);}function
convert_fields($d,$m,$N=array()){$K="";foreach($d
as$z=>$X){if($N&&!in_array(idf_escape($z),$N))continue;$ua=convert_field($m[$z]);if($ua)$K.=", $ua AS ".idf_escape($z);}return$K;}function