// * Variables & Data Types in Apex

/*

? What is a variable?
* A variable is simply a named storage/memory location that contains a value. In apex, all variables have a "data type".
! Each variable is by default initialized to null

? What is a Data Type?
* Data type is a keyword associated with a variable. It basically represents the type of data which that variable will store.
* List of primitive data types:
* 1. Boolean
* 2. Integer
* 3. Decimal
* 4. Double
* 5. Long
* 6. Date
* 7. Datetime
* 8. Time
* 9. Id
* 10. String
* 11. Object
* 12. Blob

* These are the OOTB or fundamental data types available in apex programming language. Let's talk about each one of them in detail:

? What is a Boolean data type?
* A variable of Boolean data type can store only one of these two values:
* 1. True
* 2. False

* Example of Boolean data type:
*/

/*
one
two
three

*/

// comment

// * In order to declare a variable, we follow the format: <Data Type><space><Variable name><;>
Boolean isQualified;
System.debug('Value of isQualified boolean variable is: ' + isQualified);

isQualified = false; // * Equals (=) means Assignment
System.debug('Value of isQualified boolean variable is: ' + isQualified);

isQualified = true;
System.debug('Value of isQualified boolean variable is: ' + isQualified);

// isQualified = 123;

/*

? What is an Integer data type?
* An Integer data type can store a 32-bit number with no decimal point. It can store value between -2,147,483,648 to 2,147,483,647

* Example of Integer data type:

*/

Integer sum;
System.debug('Value of sum Integer variable is: ' + sum);

sum = 1;
System.debug('Value of sum Integer variable is: ' + sum);

sum = 10;
System.debug('Value of sum Integer variable is: ' + sum);

sum = 2147483647;
System.debug('Value of sum Integer variable is: ' + sum);

sum = -2147483647;
System.debug('Value of sum Integer variable is: ' + sum);

// sum = false;

/*

? What is a Decimal data type?
* A Decimal data type variable can store a number with a decimal point.

* Example of Decimal data type:

*/

Decimal sum;
System.debug('Value of sum Decimal variable is: ' + sum);

sum = 1.0;
System.debug('Value of sum Decimal variable is: ' + sum);

sum = 1.01;
System.debug('Value of sum Decimal variable is: ' + sum);

sum = 1.234567890123456789012345678901234567890123456789;
System.debug('Value of sum Decimal variable is: ' + sum);

sum = -123456789012345678901234567890123456789012345678.9;
System.debug('Value of sum Decimal variable is: ' + sum);

//* Help Article about the field: https://help.salesforce.com/s/articleView?id=000387302&type=1, however we can have 49 digits in total for a variable of type decimal

// * Assiging integer to a decimal
sum = 123;
System.debug('Value of sum Decimal variable is: ' + sum);

// sum = true;

/*
? What is a Double data type?
* A Double data type variable can store a 64-bit number with a decimal point. It can store value between -2^63 to 2^63-1
* Example of Double data type:
*/

Double sum = 3.14;
System.debug('Value of sum Double variable is: ' + sum);

// * Use Double for less precision. For example: Scientific calculations where rounding off can be done. Use Decimal for more precision. For example: Financial calulations where there are no chances of errors. By default, currency fields in Salesforce are stored as decimals.

/*
? What is a Long data type?
* A Long data type variable can store a 64-bit number without a decimal point. It can store value between -2^63 to 2^63-1.
* Example of Long data type:
*/

Long long1 = 1000000000;  // * Valid long value without "L"
Long long2 = 9223372036854775807L;  // * Valid long value with "L" (for clarity)
System.debug('Value of long1 Long variable is: ' + long1);
System.debug('Value of long2 Long variable is: ' + long2);

// * Long can be used when we need a higher range as compared to an integer

/*
? What is a Date data type?
* A Date data type variable can store a date value without any information about time.
* Example of Date data type:
*/

Date date1 = Date.newInstance(1994, 12, 26);
System.debug('Value of date1 Date variable is: ' + date1);
System.debug('Subtracting 1 from date1 variable. Updated value = ' + (date1 - 1));
System.debug('Adding 1 to date1 variable. Updated value = ' + (date1 + 1));

Date dateFromString = Date.valueOf('1994-12-26');
System.debug('Value of dateFromString Date variable is: ' + dateFromString);

System.debug('Date in string without timestamp is: ' + String.valueOf(dateFromString));

System.debug('Today\'s Date is: ' + System.today());

// * Adding two date values
Date date1 = Date.newInstance(1994, 12, 26);
Date date2 = Date.newInstance(1994, 12, 20);
System.debug(date1 + date2);

/*
? What is a Datetime data type?
* A Datetime data type variable can store a datetime value like a timestamp.
* Example of Datetime data type:
*/

Datetime date1 = Datetime.newInstance(1994, 12, 26);
System.debug('Value of date1 Datetime variable is: ' + date1);

Datetime dateFromString = Datetime.valueOf('1994-12-26 23:11:10'); // GMT + 5:30
System.debug('Value of dateFromString Datetime variable is: ' + dateFromString);

System.debug('Date in string without timestamp is: ' + String.valueOf(dateFromString));

/*
? What is a Time data type?
* A Time data type variable can store a time value which indicates a particular time.
* Example of Time data type:
*/

Time time1 = Time.newInstance(14, 25, 60, 100);
System.debug('Value of time1 Time variable is: ' + time1);
System.debug('Value of hour: ' + time1.hour());
System.debug('Value of minute: ' + time1.minute());
System.debug('Value of second: ' + time1.second());
System.debug('Value of millisecond: ' + time1.millisecond());

/*
? What is a ID data type?
* An ID data type variable can store any valid 18-character salesforce record id.
* Example of ID data type:
*/

Id accountId = '001Hy00001D07fwIAB';
System.debug('Value of Id accountId = ' + accountId);

Id accountIdFifteenDigits = '001Hy00001D07fw';
System.debug('Value of Id accountIdFifteenDigits = ' + accountIdFifteenDigits);

accountId = '123456789123456789';

/*
? What is a String data type?
* A String data type variable can store any set of characters surrounded by single quotes. It has no limit on the number of characters, heap size limit is used instead
* Example of String data type:
*/

String name = 'SFDC Stop';
System.debug('Value of String name = ' + name);

String nameWithTrailingWhitespace = 'SFDC Stop   ';
System.debug('Value of String nameWithTrailingWhitespace = ' + nameWithTrailingWhitespace);

String emptyStringWithWhitespace = '     ';
System.debug('Value of String emptyStringWithWhitespace = ' + emptyStringWithWhitespace);

String escapeSequence = '\nSFDC\tStop \\ A blog about salesforce';
System.debug('Value of String escapeSequence = ' + escapeSequence);

String a = 'apple', b = 'mango';
System.debug(a<b);

String c = 'sfdc', d = 'Sfdc';
System.debug(c==d);

/*
? What is a Object data type?
* An Object data type variable can store value of any data type that is supported in apex. All data types inherit from object
* Example of Object data type:
*/

Object num = 10;
System.debug('Value of Object num = ' + num);

Object name = 'SFDC Stop';
System.debug('Value of Object name = ' + name);

Object num1 = 10, num2 = 20;
System.debug('Sum of Object num1 and num2 = ' + (num1 + num2));

Object num1 = 10, num2 = 20;
Integer num1Int = (Integer) num1, num2Int = (Integer) num2;
System.debug('Sum of Integer num1Int and num2Int = ' + (num1Int + num2Int));

/*
? What is a Blob data type?
* An Blob data type variable can store a collection of binary data as a single object. Blob is the short form for Binary Large Object.
* Example of Blob data type: Contents of an image. Blob can be converted to a String and String can be converted to a Blob
*/

Blob b1 = Blob.valueOf('test');
System.debug('Value of Blob b1 = ' + b1);

System.debug('Value of Blob b1 as string = ' + b1.toString());

YouTube Tutorials

Building Blocks of Apex: Variables & Data Types Explained Simply - Salesforce Apex Tutorial Part 2

Apex Gotchas! Common Variable Errors (and Writing Comments) - Salesforce Apex Tutorial Part 3

Apex Integer Data Types: Understanding Limits & Avoiding Errors - Salesforce Apex Tutorial Part 4

Unlock Precision in Apex: The Beginner Guide to Decimal Data Type - Salesforce Apex Tutorial Part 5

Apex Double, Long, Date, Datetime & Time Data Types Explained - Salesforce Apex Tutorial Part 6

Apex Id, String, Object and Blob Data Types Decoded - Salesforce Apex Tutorial Part 7

Use Case

Automation

Platform Encryption

Building a Flow

We need a Record Triggered flow which will fire when an application record is created. It'll check if an existing lead record is present with Phone = CandidatePhone__c or not. If yes, it'll tag that record with the application record. Otherwise, it'll create one new lead record using CandidatePhone__c and CandidateName__c and will tag that new lead record to our application record.

Got to Setup, search for flow, and click on the New Flow button as shown below:

You'll get the below screen:

Choose the object as Application, this flow will run when an application record is created, in After context as shown below:

Click on the Save button to save the flow. The details are provided below:

Flow Label: Tag Lead to Application

Click on Save button in the dialog to save the flow.

Now, our flow is saved. The first step is to query lead records where Phone = CandidatePhone__c. We're going to use a Get element to query records as shown below:

We only need the Lead Id here, so we're querying only that:

Problem in the Flow

Let's save the flow once by clicking the Save button. As you try to save the flow, you'll get an error as shown below:

public class LeadQueryAction {

    /**
    * This method will query leads by phone numbers and return the list of lead ids
    */
    @InvocableMethod(label='Get Leads by Phone Numbers' description='Return lead records filtered by phone numbers' category='Lead')
    public static List<Id> queryLeadsByPhoneNumbers(List<String> phoneNumbers) {
        Map<Id, Lead> leadsMap = new Map<Id, Lead>([SELECT Id FROM Lead WHERE Phone IN :phoneNumbers]);
        System.debug(phoneNumbers);
        System.debug(leadsMap.keySet());
        return new List<Id>(leadsMap.keySet());
    }
}

Our apex class is ready now, let's get back to our flow and call this method.

First of all, let's delete the Get element as we're going to query lead records using our invocable apex method now:

Click on the + icon again and search for Get Leads by Phone Numbers action as shown below:

Notice that our invocable method's label and description are visible here. Choose this action and you'll get the New Action dialog as shown below:

Label: Update new lead id on application

API Name: Update_new_lead_id_on_application

Description: This element will update the Lead__c on application with the lead id received from Create new lead action

How to Find Records to Update and Set Their Values: Use the application record that triggered the flow

Set Field Values for the Application Record: Lead__c = {!Create_new_lead}

Let's save our flow by clicking the Save button.

Flow: Bulk Testing

List<Application__c> applications = new List<Application__c>();
applications.add(new Application__c(CandidateName__c = 'Richard Hendricks', CandidatePhone__c = '9999999999'));
applications.add(new Application__c(CandidateName__c = 'Richard Hendricks', CandidatePhone__c = '9999999999'));
insert applications;

List<String> phoneNumbers = new List<String>{'9999999999','9999999999'};
System.debug(LeadQueryAction.queryLeadsByPhoneNumbers(phoneNumbers));

The third debug statement which is coming from System.debug(LeadQueryAction.queryLeadsByPhoneNumbers(phoneNumbers)); is showing the same lead id in a list instead of a set as: (00QH40000010giZMAQ). This means that the list of lead ids which is returned from our invocable method is having only one lead id, however, we passed 2 phone numbers in this method to query and get our related lead records. 

This is why our flow is failing because when our flow is running for 2 records created in the same transaction, we have 2 flow interviews. As the flow is bulkified, the phone numbers list passed to our invocable method consist of 2 phone numbers however our method returned only a single lead id in the list of ids. Therefore, The number of results (lead ids) does not match the number of flow interviews. These metrics (debug statements) are also visible in the earlier logs when we tried to create our application records as shown below:

You can see above that the phoneNumbers list has two phone numbers whereas the leadsMap.keySet() has a single lead id.

In order to make our invocable method work correctly, we need to return the list of lead ids of same size as the size of our input list i.e. the list of phone numbers. Let's fix our invocable method now.

Issue Resolution for "FlowError: The number of results does not match the number of flow interviews"

In order to fix our invocable method, we'll do the following:

1. Query our lead records.

2. Create a map of lead phone to lead id

3. Loop our phone numbers and check: If we have a lead id corresponding to the current phone number, add it to the lead ids list, otherwise, add null to the lead ids list.

4. Return the list of lead ids.

This will ensure that the order of phone numbers received and the lead ids corresponding to those phone numbers remains aligned, it's important to ensure that our flow behaves correctly. The updated code for our invocable action class is provided below:

public class LeadQueryAction {

    /**
    * This method will query leads by phone numbers and return the list of lead ids
    */
    @InvocableMethod(label='Get Leads by Phone Numbers' description='Return lead records filtered by phone numbers' category='Lead')
    public static List<Id> queryLeadsByPhoneNumbers(List<String> phoneNumbers) {
        List<Id> leadIds = new List<Id>();
        List<Lead> leads = [SELECT Id, Phone FROM Lead WHERE Phone IN :phoneNumbers];
        Map<String, Id> leadPhoneNumberToIdMap = new Map<String, Id>();
        for(Lead lead : leads) {
            leadPhoneNumberToIdMap.put(lead.Phone, (Id) lead.Id);
        }
        for(String phoneNumber : phoneNumbers) {
            if(leadPhoneNumberToIdMap.containsKey(phoneNumber)) {
                leadIds.add(leadPhoneNumberToIdMap.get(phoneNumber));
            } else {
                leadIds.add(null);
            }
        }
        return leadIds;
    }
}

As you can see above, we created a list of lead ids named leadIds. This list will store our lead ids which we'll return from our method. Then we queried the lead records as we were doing earlier. This time, we're storing it in a list named leads.

Now, we created a Map<String, Id> named leadPhoneNumberToIdMap. This map will store our lead phone number and the corresponding lead id. We looped all the queried lead records to populate this map. Finally, we looped the phone numbers which we received in our method, we then checked: if our leadPhoneNumberToIdMap contains the current phone number as a key, we'll add the corresponding lead id to the leadIds list, otherwise, we'll add null to our leadIds list. Adding null basically means that for the current phone number, we don't have any lead present in salesforce. Note that a list can have multiple null values.

Let's save our updated apex class and run the below code snippet to test our flow once again. This time we'll create 4 application records as shown below:

List<Application__c> applications = new List<Application__c>();
applications.add(new Application__c(CandidateName__c = 'Richard Hendricks', CandidatePhone__c = '9999999999'));
applications.add(new Application__c(CandidateName__c = 'Erlich Bachman', CandidatePhone__c = '9999999991'));
applications.add(new Application__c(CandidateName__c = 'Richard Hendricks', CandidatePhone__c = '9999999999'));
applications.add(new Application__c(CandidateName__c = 'Gavin Belson', CandidatePhone__c = '9999999992'));
insert applications;

If you notice above, the first and third application records have the same candidate Richard Hendricks with the same phone number as: 9999999999, so, our flow should link the existing lead to both the application records. However, the second and fourth application records have different candidates i.e. Erlich Bachman and Gavin Belson with different phone numbers. So, our flow should create new leads and link them with our application records.

Currently, we only have 2 application records in the system that we created earlier as shown below:

Now, as we execute our code snippet, we get the below output:

Notice that we got 4 new applications created as shown above. The first and third application records are linked with the same lead Richard Hendricks, however, the second and fourth records are linked with new lead records i.e. Erlich Bachman and Gavin Belson. 

This time our invocable method is working Perfectly Fine! and the flow is not failing. You can add debug statements in this method to see how it works. However, I'm displaying the output we get from our invocable method as it's called internally using the below code snippet:

List<String> phoneNumbers = new List<String>{'9999999999', '9999999993', '9999999999', '9999999994'};
System.debug(LeadQueryAction.queryLeadsByPhoneNumbers(phoneNumbers));

If you notice above, the first and third phone numbers are the same i.e. 9999999999 however, the second and fourth phone numbers are different i.e. 9999999993 and 9999999994 as was there in our application records. I didn't use 9999999991 and 9999999992 here because now we have leads present in the system linked with these phone numbers. When we execute this code snippet, the output list of lead ids which we got from our method is as shown below:

As you can see above, in our output, the first and third entry in our list is the lead id of Richard Hendricks lead and it's the same. However, the second and fourth entry in our list is coming as null because there are no leads for these phone numbers present in salesforce.

Therefore, we passed 4 phone numbers and got a list of 4 elements i.e. lead ids. Now, we can say that: The number of results match the number of flow interviews.

That's all for this tutorial everyone, I hope you liked it, let me know your feedback in the comments down below.

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Happy Trailblazing!!

Hello Trailblazers,

In this post we're going to see the solution of the error "System.DmlException: Insert failed. First exception on row 1; first error: INVALID_FIELD, Cannot specify both an external ID reference Parent and a salesforce id, ParentId: []" OR "System.DmlException: Upsert failed. First exception on row 1; first error: INVALID_FIELD, Cannot specify both an external ID reference Parent and a salesforce id, ParentId: []"

The most common scenario for this error is when we're trying to insert both the parent and child records at the same time and we're providing both - the Salesforce ID of the parent object and the parent object record reference with External ID, mentioned in the child record. Ideally we should only provide one out of Salesforce ID of parent object or parent object reference with External ID but not both. Let's have a look at an example.

Inserting Account and Contact record together

"Whenever we're performing a DML on child records, we cannot specify both the parent reference record, as well as the parent record id together, even if the parent record id is null"

Hello Trailblazers, in this post we're going to talk about the resolution of a very common error as given below:

First error: Exceeded max size limit of 12000000 OR First error: Exceeded max size limit of 6000000 

This error appears when you've exceeded the heap size limit in a single transaction. The heap size limit for a synchronous transaction is 6MB and for an asynchronous transaction is 12MB. Asynchronous transactions basically consists of batch classes, future methods and queueable apex.

How to resolve this error?

List<Account> accounts = [SELECT Id FROM Account];
// Stores 50,000 records at max - greater heap size

for(List<Account> accounts : [SELECT Id FROM Account]) {
}
// Stores 200 records at max - lesser heap size

4. Manage your code effectively using helper functions - Avoid class level variables.

void callMe()
{
    List<Account> accounts = [SELECT Id FROM Account];
    System.debug(Limits.getHeapSize()); // Coming as: 321085
}
callme();
System.debug(Limits.getHeapSize()); // Coming as: 1044

Hello Trailblazers,

Recently, I faced this issue in one of the projects I was working on. The issue was UNABLE_TO_LOCK_ROW, unable to obtain exclusive access to this record or N records, here N is just a placeholder in "N records" it can be 10, 20, 30 or even 100...200 for you. Let's have a look at the use case first and then we'll discuss the solution.

Use Case

Why it failed?

How to resolve it?