Introduction
Welcome to Part 2 of our Salesforce SOQL interview questions series!
In this post, we’ll explore 25 more questions that delve into advanced SOQL concepts, performance optimization, and best practices.
Whether you’re preparing for a technical interview or looking to sharpen your SOQL skills, this guide will help you tackle complex scenarios and write efficient queries. Let’s dive in!
Make sure to check out Part 1, Part 3, and Part 4 for the complete set of questions! 🚀
26. How do you query for records using a formula field?
Answer:
Use the API name of the formula field.
For example:
SELECT Id, Name, Formula_Field__c FROM Account
27. What is the 'USING SCOPE' clause in SOQL?
Answer:
The USING SCOPE clause is used in SOSL (Salesforce Object Search Language) to specify the search scope.
28. How do you query for records using a junction object?
Answer:
Query the junction object and use relationship fields.
For example:
SELECT Id, Account.Name, Contact.Name FROM AccountContactRelation
29. What is the 'VIEW' clause in SOQL?
Answer:
The VIEW clause is used to query list views.
For example:
SELECT Id, Name FROM Account WHERE Id IN (SELECT Id FROM Account USING VIEW = 'My_View')
30. How do you query for records using a roll-up summary field?
Answer:
Use the API name of the roll-up summary field.
For example:
SELECT Id, Name, Rollup_Field__c FROM Account
31. How do you optimize SOQL queries for performance?
Answer:
Use selective filters (indexed fields).
Avoid querying unnecessary fields.
Use
LIMITandOFFSETfor pagination.Avoid using
LIKEwith leading wildcards.
32. What is a selective query in SOQL?
Answer:
A selective query uses indexed fields in the WHERE clause to improve performance.
33. What is the maximum number of records returned by a SOQL query?
Answer:
The maximum number of records returned by a SOQL query is 50,000.
34. How do you handle large data sets in SOQL?
Answer:
Use batch processing, LIMIT, and OFFSET to handle large data sets.
35. What is the impact of using ORDER BY on query performance?
Answer:
Using ORDER BY on non-indexed fields can impact query performance.
36. How do you write a SOQL query in Apex?
Answer:
Use the Database.query() method or inline SOQL. For example:
List<Account> accounts = [SELECT Id, Name FROM Account];
37. What is dynamic SOQL?
Answer:
Dynamic SOQL is a query constructed at runtime using string concatenation. For example:
String query = 'SELECT Id, Name FROM Account';
List<Account> accounts = Database.query(query);
38. How do you prevent SOQL injection in Apex?
Answer:
Use binding variables and avoid string concatenation. For example:
String name = 'Acme';
List<Account> accounts = [SELECT Id, Name FROM Account WHERE Name = :name];
39. What is the difference between Database.query() and inline SOQL?
Answer:
Inline SOQL is written directly in Apex code.
Database.query()is used for dynamic SOQL.
40. How do you handle query exceptions in Apex?
Answer:
Use try-catch blocks. For example:
try {
List<Account> accounts = [SELECT Id, Name FROM Account];
} catch (QueryException e) {
System.debug('Query Exception: ' + e.getMessage());
}
SOQL and Governor Limits
41. What is the SOQL query limit in Apex?
Answer:
The SOQL query limit in Apex is 100 synchronous queries and 200 asynchronous queries per transaction.
42. How do you avoid hitting SOQL query limits?
Answer:
Use bulkified code.
Avoid queries inside loops.
Use collections to store query results.
43. What is the impact of SOQL queries on heap size?
Answer:
Large query results can consume heap size, leading to governor limit exceptions.
44. How do you query large data sets without hitting governor limits?
Answer:
Use batch Apex or Database.getQueryLocator().
45. What is the Database.getQueryLocator() method?
Answer:
It is used in batch Apex to handle large data sets. For example:
Database.QueryLocator ql = Database.getQueryLocator('SELECT Id, Name FROM Account');
SOQL and Custom Settings
46. How do you query custom settings in SOQL?
Answer:
Use the custom setting object name. For example:
SELECT Id, Name FROM Custom_Setting__c
47. What is the difference between list and hierarchy custom settings in SOQL?
Answer:
List custom settings are queried as a list.
Hierarchy custom settings are queried based on user or profile.
48. How is SOQL used in Salesforce reports?
Answer:
SOQL is not directly used in reports, but report filters are similar to SOQL WHERE clauses.
49. How do you query for records where a specific field is not empty?
Answer:
Use the != null condition in the WHERE clause to filter records where a specific field is not empty. For example:
SELECT Id, Name FROM Account WHERE Phone != null
This query retrieves Account records where the Phone field is populated.
50. How do you query for records where a specific field matches a pattern but is case-insensitive?
Answer:
Use the LIKE operator with the LOWER() function to perform a case-insensitive pattern match. For example:
SELECT Id, Name FROM Account WHERE LOWER(Name) LIKE '%acme%'
This query retrieves Account records where the Name field contains “acme” in any case (e.g., “Acme”, “ACME”, “acme”).
You’ve just explored the Second Set of 25 SOQL interview questions to aid in your preparation. As part of our 100 SOQL interview questions series, we’ve divided them into four parts.
Make sure to check out Part 1, Part 3, and Part 4 for the complete set of questions! 🚀
Conclusion
With these 25 advanced SOQL questions, you’re now equipped to handle complex queries, optimize performance, and work with advanced features like polymorphic fields and custom metadata types.
In Part 3, we’ll learn some more challenging questions and practical tips to ace your Salesforce interview. Keep practicing, and you’ll be SOQL-ready in no time!
