Hi,

I have to write a trigger to show error message when quantity more than actual quantity value.

i have 2 objects callup order(child) and purchase order(parent) both have lookup,

in purchase order a filed called quatition qunatiyty ,here i will give my qty.

so for one purchase order i can i create any number of call up order,

for example i given qty 200 in purchase order,

now when i goto create call up order it should not allow me to create more than 200,

example i created one call up order with qty 120,i created anther call up order with 70,and when i try to craete anther call up order with qty 30 i need to show error.

can any one tell me how can i do this

this my trigger
 

trigger total_calluo_order_qty on Call_Up_Order__c (before insert,before update) {

set<id> saleid=new set<id>();
List<Purchase_Order__c> ToUpdate = new List<Purchase_Order__c>();

if(trigger.isInsert || trigger.isUpdate){
for(Call_Up_Order__c c: trigger.new){
      saleid.add(c.Sale_Confirmation_Order__c);
    }
}

if(trigger.isDelete){
    for(Call_Up_Order__c c: trigger.new){
      saleid.add(c.Sale_Confirmation_Order__c);
    }
  }

map<id,double> Map = new map<id,double>();
for(AggregateResult q : [select sum(Call_Up_Quantity__c)totalcallup,Sale_Confirmation_Order__c from Call_Up_Order__c where Sale_Confirmation_Order__c in:saleid group by Sale_Confirmation_Order__c])
{
      Map.put((Id)q.get('Sale_Confirmation_Order__c'),(Double)q.get('totalcallup'));
  }


   for(Purchase_Order__c p:[select id,Total_call_up_order_Quantity__c from Purchase_Order__c where id in:saleid])
   {
    Double PaymentSum = Map.get(p.Id);
    p.Total_call_up_order_Quantity__c=PaymentSum ;
    ToUpdate.add(p);
    }         
         update ToUpdate;
             
         
         for(Call_Up_Order__c cup:[select id,Quote_Quantity__c,Balance_Qty__c,Call_Up_Quantity__c,Total_call_up_order_Quantity__c from Call_Up_Order__c  where id in:trigger.new])
         {
         if(cup.Total_call_up_order_Quantity__c >= cup.Quote_Quantity__c)        
         {
         cup.addError('please check all call up order quantity was excedded');
         }         
         }
         
}

regards

venkatesh.