require(['N/search']);
var search = require('N/search');
var customerSearchObj = search.create({
   type: "customer",
   filters: [
      ["isinactive","is","F"], 
      ["AND"]
      ["parentcustomer.internalidnumber","isempty",""]
   ],
   columns: [
      "internalid",
      "phone",
      "email",
      "shipaddress1"
   ]
});
var searchResultCount = customerSearchObj.runPaged().count;
customerSearchObj.run().each(function(result){
   // .run().each has a limit of 4,000 results
   return true;
});