Query DB using apex in salesforce

Question

com and apex triggers

I have two objects namely Customer_c and Order_c I am trying to write a trigger to delete an order entry belonging to a customer who has been made inactive.

Basically i want to trigger on update for customer_c table

retrieve an entry from customer_c where the Active_c( boolean value) has been made false upon update and take that customers 'Name' and look up in the Order_c table and delete all the 'Name'(Orders) belonging to that customer.

Below is my trigger code. when I am trying to save the trigger in salesforce. I get the following error:

Error: Compile Error: unexpected token: 'res2' at line 13 column 19

Could anyone please help me on this?

trigger NewCustomerActive on Customer__c(after update) {
  List<Customer__c> res2 = 
        [SELECT Name FROM Customer__c j WHERE j.Active__c = false];
  List<Order__c> res = 
        [SELECT Name FROM Order__c WHERE Customer__c = res2];
}

Answer 1

Change it to

trigger NewCustomerActive on Customer__c(after update) {
  List<Customer__c> res2 = 
        [SELECT Name FROM Customer__c j WHERE j.Active__c = false];
  List<Order__c> res = 
        [SELECT Name FROM Order__c WHERE Customer__c in:res2];
}

Answer 2

Or if you want to save soql statements:

trigger NewCustomerActive on Customer__c(after update) {
  List<Order__c> res = 
        [SELECT Name FROM Order__c WHERE Customer__r.Active__c = false];
}