Gets Maps from SOQL Query salesforce

As we all know, Apex code has limitation of  Number of code statements that can be executed. While writing Apex code, we should take care of number of code statement that are  executed to avoid governor limits. It is useful to understand how to reduce the number of executed code statements so that we can stay within the governor limits.

Normally we get list of records in a SOQL query.Sometime we also need set of id’s or map of record id’s and record or list of record id’s.

Apes code for above requirement will be as below:

//Creating List of all account Ids
List<id> accIdsList = new List<id>() ;

//Creating set of all account Ids
Set<id> accIdsSet = new Set<id>() ;

//Creating Map with account id as key and account record as value
Map<Id,Account> accountIdObjMap = new Map<Id,Account>();

//Fetching all accounts
List<account> accList = [select Id,name,site,rating,AccountNumber from account limit 50000] ;

//Fetching Account ids
for(Account acc : accList){
	accIdsSet.add(acc.id);
	accIdsList.add(acc.id);
	accountIdObjMap.put(acc.id,acc);
}

In the code above, if there are large number of records(say 50000) then for loop will be executed 50000  times and also every line in for loop will be executed 50000 times. We can avoid this unnecessary for loop by using good SOQL query which will return map instead of list. After that we can easily get list of accounts or set of account Id’s or List of account Id’s using methods.

New Apex Code will be as below:

//Creating List of all account Ids
List<id> accIdsList = new List<id>() ;

//Creating set of all account Ids
Set<id> accIdsSet = new Set<id>() ;

//Fetching all accounts
List<account> accList = new List<Account>();

//Creating Map with account id as key and account record as value
Map<Id,Account> accountIdObjMap = new Map<Id,Account>([select Id,name,site,rating,AccountNumber from account limit 50000]);

//getting list of account using map.values method
accList = accountIdObjMap.values();

//getting set of account Id's using map.keySet method
accIdsSet = accountIdObjMap.keySet();

//getting list of account Id's using list.addAll method
accIdsList.addAll(accIdsSet);

External Key in Salesforce

External Key is a very interesting and important feature given by Salesforce. It is very much helpful when we are importing some data from legacy system, means suppose the data in the old system needs to be migrated to salesforce and we want to avoid importing any duplicate records from that system into salesforce.

Then, how salesforce will come to know that on which basis, it should differentiate between the records being imported from external system.

For this purpose, we can define some field from legacy data that will act as unique identifier in salesforce and we can map that field with a custom field in salesforce that has attribute External Id true. So, whenever we will import data from legacy system, salesforce won’t allow any duplicate record based on the external id defined for that object.

We can define 3 external Ids for every object, and only three data types are allowed to be used in external id. These are (Email, text, number).

So, for example there are some records existing in external system. Please see the screenshot below:

Suppose these are records in external system and needs to be imported in salesforce and you want that duplicate records should not be imported in salesforce. So, we need to define some field on basis of which salesforce can decide which record is duplicate and which is not. So, in above screenshot we have picked Type to be an external id. Hence, salesforce won’t allow all the records highlighted in black border in the snapshot above because it will categorize them as duplicate record because one record with that particular Type value has already been imported(highlighted in red).

That is the importance of external Id while integrating with external systems. If you are working with external system, external id will become your best friend.

Visualforce page render as pdf example

We can render any page as pdf  by adding renderAs attribute to <apex:page> and specifying “pdf” as value. renderAs value is name of any supported content converter. Currently PDF is the only supported content converter. Setting renderAs attribute to “pdf” renders the page as a PDF.

Rendering a Visualforce page as a PDF is intended for pages that are designed and optimized for print. Standard components that are not  easily formatted for print or contain form elements like inputs, buttons, any component that requires Javascript to be formatted, should not be used.  We should always verify the format of your rendered page before deploying it.

Sometimes PDF fails to display all the characters properly. In that case we should adjust the fonts in our CSS to use a font that supports our needs. We can use style element for displaying content properly in PDF.

In the example below, we are showing 10 account in table in visualforce page which is renderAs “pdf”. We are just adding renderAs attribute in apex:page and giving “pdf” as its value.

Click for Demo

Visualforce Page

<apex:page controller="PdfExampleController" renderAs="pdf">
  <apex:form >
    <apex:pageBlock >
        <apex:pageBlockTable value="{!accList}" var="acc" border="2">
           <apex:column value="{!acc.name}"/>
           <apex:column value="{!acc.annualrevenue}"/>
           <apex:column value="{!acc.type}"/>
           <apex:column value="{!acc.accountnumber}"/>
           <apex:column value="{!acc.rating}"/>
        </apex:pageBlockTable>
    </apex:pageBlock>
  </apex:form>
</apex:page>

Apex Code:

public with sharing class PdfExampleController {
    public List accList{get;set;}
    public PdfExampleController (){
        accList = [select id,name,type,accountnumber,annualrevenue,Rating from account limit 10];
    }
}

Please note that this page is not optimized to be renderAs pdf. Salesforce has provided Best Practices for Rendering PDFs.

Salesforce record id hack first 3 digit

This post is going to be interesting. As we all know that each record in salesforce is identified by record id which is unique for every organisation. Salesforce record id can be 15 digit case sensitive or 18 digit case insensitive. Last three digits of 18 digit record id provide checksum of first 15 digits.

Now interesting and important point is that first 3 digits of record id determines SObject type of record. For every salesforce object first 3 digit of record id is unique. And for all standard salesforce objects, first 3 digits of record id is constant. For example, for standard Account object first 3 digit of record id is 001. Similarly for Contact object first 3 digit is 003. These first three digit of record id is known as ‘Record id prefix’.

For each custom object also, first 3 digit of record id is unique.

Trick 1:
Remembering these 3 digits of object’s record id is very useful. When we will enter first 3 digits of record id after instance URL we will be on List view page for that particular object.

Trick 2:

We can also directly go to any object tab if we remember first 3 digit of object’s record id. For example, as we know first 3 digits of Account object’s record id is 001. So if we will enter ‘001/o ‘ after instance URL, we will land to Account tab. In similar way we can go to any tab if we know or remember first 3 digits of record id.

actionRegion visualforce salesforce

actionRegion provides an area of a Visualforce page that decides and separates which components should be processed by the force.com server when an AJAX request is generated. Only the components which are inside actionregion component are processed by server, so it increases visualforce page performance. Here components means, all visualforce tags like inputField, outputField, outputPanels etc.

actionregion is one of the most important tag which helps in increasing page performance. So we should try to make maximum use of actionregion in visualforce page. actionRegion component only defines which components the server processes during a request, it does not define which of the page are re-rendered when the request completes. We will still use reRender attribute on action component to decide area which should be rerendered AJAX request completes.

One more important point to note is that even when we use <apex:actionRegion> component, whole form is still submitted but only area which is inside actionRegion is processed by server.

I will explain importance of actionRegion with help of two examples. First example will not use actionRegion and second example will use actionRegion. Here in both example we are trying to show phone textbox, when we are selecting customer priority as high.

Example 1 Without <apex:actionRegion>

Click for demo without actionRegion

In this example, we are trying to show phone textbox when we are selecting high customer priority, then we are getting error as SLA and Account name is required. So validation fails.

Visualforce Page:

<apex:page controller="withoutActionregionController" tabStyle="Account">
    <apex:form id="myform">
        <apex:pageBlock id="pageId">
            <apex:pageBlockSection title="If you will select High Customer Priority then phone textbox will be shown" columns="1" id="out" collapsible="false">
                
                <apex:pageBlockSectionItem >
                    <apex:outputLabel value="{!$ObjectType.Account.fields.CustomerPriority__c.label}" for="priority"/>
                    
                    <apex:inputField value="{!acc.CustomerPriority__c}" id="priority" >
                        <apex:actionSupport action="{!priorityChanged}" reRender="pageId" event="onchange"/>
                    </apex:inputField>
                </apex:pageBlockSectionItem>
                
                <apex:inputField value="{!acc.Phone}" rendered="{!showPhone}"/>
            </apex:pageBlockSection>  
            
            <apex:pageBlockSection title="Other Account Details" columns="2" collapsible="false">
                <apex:inputField value="{!acc.SLA__c}" required="true"/>
                <apex:inputField value="{!acc.Rating}"/>
                <apex:inputField value="{!acc.name}"/>
            </apex:pageBlockSection>  
        </apex:pageBlock>
    </apex:form>
</apex:page>

Apex Code:

public class withoutActionregionController {
    public Account acc{get;set;}
    public Boolean showPhone{get;set;}
    
    public withoutActionregionController(){
        acc = new Account();
        showPhone = false;
    }
    
    public PageReference priorityChanged(){
        if(acc.CustomerPriority__c == 'High'){
            showPhone = true;
        }
        else{
            showPhone = false;
        }
        return null;
    }
}

Now in second example we will use same code but with actionRegion tag. So in second example no validation error will be returned as only code inside actionregion component is processed by server.

Example 2 with <apex:actionRegion>

Click for demo with ActionRegion

Visualforce Page:

<apex:page controller="withActionregionController" tabStyle="Account">
    <apex:form id="myform">
        <apex:pageBlock id="pageId">
            <apex:pageBlockSection title="If you will select High Customer Priority then phone textbox will be shown" columns="1" id="out" collapsible="false">
                
                <apex:pageBlockSectionItem >
                    <apex:outputLabel value="{!$ObjectType.Account.fields.CustomerPriority__c.label}" for="priority"/>
                    
                    <apex:actionRegion >
                    <apex:inputField value="{!acc.CustomerPriority__c}" id="priority" >
                        <apex:actionSupport action="{!priorityChanged}" reRender="pageId" event="onchange"/>
                    </apex:inputField>
                    </apex:actionRegion>
                </apex:pageBlockSectionItem>
                
                <apex:inputField value="{!acc.Phone}" rendered="{!showPhone}"/>
            </apex:pageBlockSection>  
            
            <apex:pageBlockSection title="Other Account Details" columns="2" collapsible="false">
                <apex:inputField value="{!acc.SLA__c}" required="true"/>
                <apex:inputField value="{!acc.Rating}"/>
                <apex:inputField value="{!acc.name}"/>
            </apex:pageBlockSection>  
        </apex:pageBlock>
    </apex:form>
</apex:page>

Apex Code:

public class withActionregionController {
    public Account acc{get;set;}
    public Boolean showPhone{get;set;}
    
    public withActionregionController(){
        acc = new Account();
        showPhone = false;
    }
    
    public PageReference priorityChanged(){
        if(acc.CustomerPriority__c == 'High'){
            showPhone = true;
        }
        else{
            showPhone = false;
        }
        return null;
    }
}

Difference between Export & Export All in data loader is really interesting.

I was asked this question in one of my job interview.

Export and Export All

There are two buttons available in dataloader ‘Export’ & ‘Export All’. Difference in both button functionality is very small. When we use ‘Export’ button for any object in salesforce, all records( excluding records present in Recycle Bin) present in the system for that particular object are exported to a .csv file. But when we use Export All, all records (including records present in Recycle Bin) for that particular object are exported to a .csv file. Deleted records present in recycle bin are also called ‘soft Deleted’ records.

When you choose fields to be extracted using data loader, you can select IsDeleted field as well because it tells which record is soft deleted and which is not.

IsDeleted

(IsDeleted = true) –> record has been soft deleted.

(IsDeleted = false) –> record has not been deleted.

I clicked on Export All and in the screenshot below, you can see there are some records for which IsDeleted is true. These are some records that were present in recycle bin(soft deleted).

For more reference on data loader, Go to Data Loader Reference