What is the problem we will face if we dont use external id while using data migration

SOQL query to count the no of record types present in a page

Can anyone suggest where can I get scenario based questions for interviews of different SFDC concepts ?

Challenge Not yet complete... here's what's wrong:
Executing the 'generateStringArray' method failed. Either the method does not exist, is not static, or does not return the proper number of strings.

My code is:
public class StringArrayTest {
    
    public static List<String> generateStringArray(Integer l)
    {
     List<String> a1=new List<String>();
        for(i=0;i<l;i++)
        {
            a1.add('Test '+i);
            System.debug(a1[i]);
        }
        return a1;
    }

} 
m executing through
StringArrayTest em = new StringArrayTest();
em.generateStringArray(5);

Can anyone help me whats wrong I did here?

Can anyone suggest where can I get scenario based questions for interviews of different SFDC concepts ?

Can anyone suggest where can I get scenario based questions for interviews of different SFDC concepts ?