Hi,I am new to apex language,I want to learn apex language with my own. I have some good knowledge on java..But I am getting confuse to learn apex language,so I want to learn apex step by step,If there is any material is available for apex please let me know,instead of work book. Already I have seen work books.

How to learn Apex language in a proper way.

public class UpdateField {
    public static void upd(List<Customer__c> c)
    {
        for(Customer__c p:c)
        {
            if(p.MRRMonthly__c!=CustomerInfo__c.MRR__c)
            {
                p.MRRMonthly__c=CustomerInfo__c.MRR__c;
            }
        }
    }
}

I am getting an error:   Error: Compile Error: Illegal assignment from Schema.SObjectField to Decimal at line 8 column 17

trigger FieldUpdate on Customer__c (before insert,before update) {
    if(Customer__c.MRRMonthly__c!=CustomerInfo__c.MRR__c)
    {
        Customer__c.MRRMonthly__c=Customer__c.MRR__c;
    }

}

I am getting an error like this:

Error: Compile Error: Expression cannot be assigned at line -1 column -1. can any help me to solve this.

Can we give relationship like this in salesforce.If it is possible please let me know how is it possible.

I am trying to create a workflow rule with 3 objects.for example I have 3 objects,they are Customer,CustomerInfo,SurveyResponse.Customer is a parent,In Customer object I have 3 fields,are AccountNumber,Description and MRR,and in CustomerInfo I have 2 fields(Description and MRRMonthly),and I have 1 field(NPSScore) in SurveyResponse...Now I am trying to give a workflow rule for email alert when the condition is satisfied. condition is

IF(SurveyResponse__c.NPSScore__c<=5&&CustomerInfo__c.MRRMonthly__c<=1000)

Note:we should not have a relationship b/w CustomerInfo and SurveyResponse

I am trying to create a workflow rule with 3 objects.for example I have 3 objects,they are Customer,CustomerInfo,SurveyResponse.Customer is a parent,In Customer object I have 3 fields,are AccountNumber,Description and MRR,and in CustomerInfo I have 2 fields(Description and MRRMonthly),and I have 1 field(NPSScore) in SurveyResponse...Now I am trying to give a workflow rule for email alert when the condition is satisfied. condition is

condition:we should not have a relationship b/w CustomerInfo and SurveyResponse

IF(SurveyResponse__c.NPSScore__c<=5&&CustomerInfo__c.MRRMonthly__c<=1000)

How can we give one parent and two children relationship

Can we give relationship like this in salesforce.If it is possible please let me know how is it possible.

I am trying to create a workflow rule with 3 objects.for example I have 3 objects,they are Customer,CustomerInfo,SurveyResponse.Customer is a parent,In Customer object I have 3 fields,are AccountNumber,Description and MRR,and in CustomerInfo I have 2 fields(Description and MRRMonthly),and I have 1 field(NPSScore) in SurveyResponse...Now I am trying to give a workflow rule for email alert when the condition is satisfied. condition is

condition:we should not have a relationship b/w CustomerInfo and SurveyResponse

IF(SurveyResponse__c.NPSScore__c<=5&&CustomerInfo__c.MRRMonthly__c<=1000)

How can we give one parent and two children relationship