ServiceContext.CreateQuery Not Returning All Key / Value Pairs

CMR 2013 On Premise

Hello,

I am querying the customeraddress entity and updating several values...or trying to.

When a lead is created the user may not have a city in the address field. When the lead is saved the address is saved. Later when the system tries to update the city in a plugin I use this line to obtain the address

var res = from z in ServiceContext.CreateQuery("customeraddress")

Problem is that since the city field is empty it drops the city key / value pair and thus when I go to update it doesn't exists. Is there a way I can tell the service context to get me all keys / value pairs (aka db columns)?

TIA

Full code snippet in case above is not enough context:

 //query to get address records
var res = from z in ServiceContext.CreateQuery("customeraddress")
where z["parentid"].Equals(AddyContactId)
select z;

foreach (var c in res)
{
   Entity e = (Entity)c;

    //here I go to find / update the city key only it is not there

}