I got a flat/puncture on my bike tube, how can I fix it myself without going to the nearest bike shop? What kind of equipment would I need?


Question: where is the missing , before statement?
Answer: Try escaping the "in your url string:

var url= "contr_entry_pkg.sales_center_dropdown?&amp;pnSalesCenterID=document.getElementById(\"pnSalesCenterID\").value +&amp;pvCurrCd='||CURRDEF||'";


That will fix the syntax error, although I think you meant something like this:

var url= "contr_entry_pkg.sales_center_dropdown?&amp;pnSalesCenterID=" + 
         document.getElementById("pnSalesCenterID").value +
         "&amp;pvCurrCd='||CURRDEF||'";


Also, you should (though it's not strictly required) place semi-colons after each statement:

ajaxReq = (window.XMLHttpRequest)? new XMLHttpRequest() : new ActiveXObject("MSXML2.XMLHTTP"); // &lt;-- added ; here
...
ajaxReq.send(); // &lt;-- added ; here