AlwaysThinkin

@isTest
public static TestMethod void DataTypes(){

        string text1 = 'this text';
        string text2 = 'that text';
        
        string text3 = text1 + text2;
        System.debug(text3);
        text3 = text3 + 'more text';
        System.debug(text3);

AlwaysThinkin

trigger ContactAfterTrigger on Contact (after insert) {
    List<Contact> consToUpdate = new List<Contact>();
    
    for(Contact conInTrigger : trigger.new){
        Contact c = new Contact();//Create a new instance of an as-yet-unidentified Contact
        		c.Id = conInTrigger.Id;//Set that Contact's ID to an existing ID from the Contacts in Trigger.new 
        		c.Department = 'IT';//Change a field value on that Contact
        consToUpdate.add(c);//Add it to our List so we can update it later when all Contacts in Trigger.new have been prepared
    }
    update consToUpdate;//Perform the DML update call outside of our for-loop to avoid Governor Limits (150 DML per transaction)!

AlwaysThinkin

trigger ContactCompareTrigger on Contact (after update) {
//Create an empty Map of Contacts for eventual updates
    Map<ID, Contact> consToUpdate = new Map<Id, Contact>();

    //This is a very common pattern for iterating over the list of records
    //We use the size() method for Lists to handle each Contact in Trigger.new 
    
    for(Integer i = 0 ; i < trigger.new.size() ; i++){
        Contact old = trigger.old[i];
        Contact nw = trigger.new[i];//We cannot use "new" as our variable name, it's a reserved word.

AlwaysThinkin

trigger LeadTrigger on Lead (After Update) {
    Map<ID, Lead> leadsToUpdate = new Map<ID, Lead>();//Create a Map to hold eventual updates
    
    //This is a very common pattern for iterating over the list of records
    //We use the size() method for Lists to handle each Lead in Trigger.new 
    
    for(Integer i = 0 ; i < trigger.new.size() ; i++){
        Lead old = trigger.old[i];
        Lead nw = trigger.new[i];//We cannot use "new" as our variable name, it's a reserved word.
        

AlwaysThinkin

@isTest
public class DataTypeTestAnswers {
    public static TestMethod void DataTypes(){
        
        string text1 = 'this text';
        string text2 = 'that text';
        
        string text3 = text1 + text2;
        System.debug(text3);
        text3 = text3 + 'more text';

AlwaysThinkin

@isTest
public class Collections {
    static testMethod void Lists(){
        //LISTS ARE AN ORDERED COLLECTION OF DATA
        
        //How to instantiate a List with some pre-defined values
        String someword = 'thread';
        List<String> threeStrings = new List<String>{'rope', 'twine', someword};
        
        //Lists have methods that allow us to evaluate or manipulate them

AlwaysThinkin

@isTest (seeAllData = true)
public class SOQLqueries {
    static testMethod void relationshipQueries(){
        
        //Child-to-Parent queries are easy. Simply use the API Name of the lookup field to the parent object
        //and use dot notation to specify the field on that object you want
        List<Contact> conAccts = [SELECT FirstName, LastName, Account.Name FROM Contact];
        
        //FIX ME! Use a query with a WHERE filter to only return Contacts from the Account named 'sForce'
        //List<Contact> sForceconAccts = ???

AlwaysThinkin

@isTest
public class CollectionsAnswers {
    static testMethod void Lists(){
        //LISTS ARE AN ORDERED COLLECTION OF DATA
        
        //How to instantiate an List with some pre-defined values
        String someword = 'thread';
        List<String> threeStrings = new List<String>{'rope', 'twine', someword};
        
        //Lists have methods that allow us to evaluate or manipulate them

AlwaysThinkin

/* This Apex Class is a Unit Test Class and all the code can be checked by running the test.
* Copy this into a new Apex Class named "ControlFlow" and save it.
* As you read through it, look for "FIX ME!" and make the changes suggested.
* If your changes are correct all the tests (System Asserts) will pass.
* 
* You can also see what's happening in the Logs by opening a Log and checking the Debug Only box
* you can compare the line numbers in the Log to the line number in the Class to find a specific
* debug entry.
*/

AlwaysThinkin

/* This Apex Class is a Unit Test Class and all the code can be checked by running the test.
* Copy this into a new Apex Class named "ControlFlow" and save it.
* As you read through it, look for "FIX ME!" and make the changes suggested.
* If your changes are correct all the tests (System Asserts) will pass.
* 
* You can also see what's happening in the Logs by opening a Log and checking the Debug Only box
* you can compare the line numbers in the Log to the line number in the Class to find a specific
* debug entry.
*/