Avoid Governor Limits

Salesforce is based on Multiteanet Architecture so they have imposed limits for the implementation of the Apex and customization of things. So the first and foremost challange in front of each developer is “Implementation of code avoiding governor limits”. So below are some tips and tricks to avoid governor limits
The governor limits are applied on the basis of the initiation of the code execution. The execution initiates from :-
  1. Apex Trigger
  2. Apex Web Service
  3. Anonymous Block
  4. Visualforce Controller
DML operations are basic needs of any implementation. so lets discuss the problem and the solution for this.
1.) Let’s have a look at the type of code that could cause this issue
public void functionName(List theNames){
for(String theName: theNames){
myObject__c obj = [SELECT processed__c FROM myObject__c WHERE name=:theName]; //This may result in ‘Too many SOQL queries’
obj.processed__c = true;
update obj; // Mistake #2 – may result in ‘Too many DML rows’
}
}
The SELECT statement will be run for each iteration of the loop i.e. a list of 200 names means 200 queries, which means 200 round trips, which means this isn’t going to work. The solution is to fetch all records for the object before the loop and then loop through the list of objects returned, thereby bypassing the need to query each time.
Solution :-
public void rhymeWithOrange(List theNames){
List objToUpdate = new List(); // intermediate list
List objects = [SELECT processed__c FROM myObject__c];
for(String myName: theNames){
for(myObject__c obj: objects){
if(theName==obj.name){
obj.processed__c = true;
objToUpdate.add(obj); // add processed objects to intermediate list
}
}
}
update objToUpdate; // update all objects at once to avoid SOQL execption
}
In above what we did is made a list of updated objects and then updated all in a single update statement just 1 statement.
There are other solution as well dependent on the situation which we will cover later such as Batchapex,Future Calls


Source : http://www.saasanalogy.com/avoid-governor-limits/

Comments

Post a Comment

Popular posts from this blog

Salesforce.com: Expression Operators in Salesforce lightning Components

Image
Generally In every component implementation we have a need to  change the UI conditionally, or show/hide a section/column based on certain conditions. We need simple ways to do this instead of having every handler in code. Below are key operators and their syntax to handle any such situation Ternary Operator This expression uses the ternary operator to conditionally output one of two values dependent on a condition. 1 <a class="{!v.location == '/active' ? 'selected' : ''}" href="#/active">Active</a> The {!v.location == ‘/active’ ? ‘selected’ : ”} expression conditionally sets the class attribute of an HTML <a> tag, by checking whether the location attribute is set to /active . If true, the expression sets class to selected . Using <aura:if> for Conditional Markup <aura:attribute name="edit" type="Boolean" default="true"/> <aura:if isTrue=&qu
Read more

Custom Calendar on VisualForce Page

Image
There has always been a need to have a calendar component for visualforce page this kind of component can be used in events booking,events calendar,scheduling requirements and all the places where we need to show events by dates. This can be easily implemented using jquery,fullcalendar plugin and json in apex. So what we need here is 1.) Fullcalandar plugin  Download 2.) A custom object with start dates and end dates for events 3.) Apex class to pull data from object and convert that into json using json.serailze First we have to upload the fullcalendar lib to static resource and then we have to create a visualforce page with below code. The important thing is "JSONOFLIST" which is just json created from list of records by using JSONOFLIST = JSON.serialize(LIST OF SOBJECT); It will give you a calendar with items highlited on page Source : http://www.saasanalogy.com/custom-calendar-on-visualforce-page/
Read more

Salesforce.com: Scheduled Apex

The Apex Scheduler lets you delay execution so that you can run Apex classes at a specified time. This is ideal for daily or weekly maintenance tasks using Batch Apex. To take advantage of the scheduler, write an Apex class that implements the Schedulable interface, and then schedule it for execution on a specific schedule. Scheduled Apex Syntax To invoke Apex classes to run at specific times, first implement the Schedulable interface for the class. Then, schedule an instance of the class to run at a specific time using the System.schedule method. global class SomeClass implements Schedulable { global void execute(SchedulableContext ctx) { // awesome code here } } The class implements the Schedulable interface and must implement the only method that this interface contains, which is the execute method. The parameter of this method is a SchedulableContext object. After a class has been scheduled, a CronTrigger object is created that represents the scheduled job. It p
Read more