Nasıl pl sql için bir php fonksiyon json_encode yapmak için?

$.ajax({
                    url:"db_sotr_file.anketa_my.cookiecheckjava",
                    global:false,
                    type:"POST",
                    data:({sessionid: Get_Cookie('sessionid'), hashid: Get_Cookie('hashid')}),
                    dataType:"html",
                    async:false,
                    success: function(data){
                        if(data == 'error') alert('Refresh Site ))))) bolmady');
                    }
                });

I did a ajax request to the html page written in pl sql, which in turn returns the "er ..." instead of "error". And now I think instead of html dataType: "html" to use json. But in pl sql no such function.