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Comprehensive and Detailed Explanation From Exact Extract:

To determine which SOQL queries are safe from SOQL injection, we need to evaluate each option for how it handles the name parameter (user input from a Visualforce page) and whether it properly mitigates the risk of SOQL injection. SOQL injection occurs when untrusted user input is directly embedded into a query string, allowing malicious users to manipulate the query’s logic. Let’s analyze each option systematically, referencing Salesforce’s official documentation, particularly the Secure Coding Guidelines and Apex Developer Guide.

Understanding SOQL Injection:

SOQL Injection: This vulnerability arises when user input is dynamically concatenated into a SOQL query string without proper sanitization, allowing an attacker to alter the query’s behavior. For example, if name is ' OR '1'='1, an unsafe query might return all records instead of the intended subset. The Salesforce Secure Coding Guidelines state: “SOQL injection occurs when untrusted input is concatenated into a query string, potentially allowing an attacker to bypass intended logic” (Salesforce Secure Coding Guidelines, SOQL Injection).

Prevention Techniques:

Bind Variables (:variable): Using bind variables in SOQL queries ensures user input is treated as a value, not part of the query logic, preventing injection. The Apex Developer Guide notes: “Using bind variables (:variable) in SOQL queries is the safest way to prevent SOQL injection” (Salesforce Apex Developer Guide, Secure Coding for SOQL).

Sanitization: If dynamic SOQL (e.g., Database.query()) is used, user input must be sanitized using methods like String.escapeSingleQuotes() to escape special characters (e.g., single quotes) that could alter the query.

Context: The name variable comes from a Visualforce page, meaning it’s untrusted user input and must be handled carefully to prevent injection.

Evaluating the Options:

A.

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String query = '%' + name + '%';

List results = [SELECT Id FROM Account WHERE Name LIKE :query];

Approach: Constructs a query string by concatenating wildcards (%) with the name variable, then uses a bind variable (:query) in the SOQL query.

Security: Using a bind variable (:query) ensures that the value of query (which includes name) is treated as a literal value in the LIKE clause, not as part of the query’s syntax. Even if name contains malicious input (e.g., ' OR '1'='1), the SOQL engine treats it as a single string to match against Name, preventing injection. The Apex Developer Guide confirms: “Bind variables prevent SOQL injection by treating user input as data, not executable code” (Salesforce Apex Developer Guide, Secure Coding for SOQL).

Example: If name = 'Test' OR '1'='1, then query = '%Test' OR '1'='1%'. The SOQL query becomes:

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[SELECT Id FROM Account WHERE Name LIKE '%Test\' OR \'1\'=\'1%']

This searches for records where Name matches the literal string %Test' OR '1'='1%, which is safe and does not alter the query logic.

Conclusion: Safe from SOQL injection due to the use of a bind variable.

B.

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String query = 'SELECT Id FROM Account WHERE Name LIKE \'%' + name.noQuotes() + '%\'';

List results = Database.query(query);

Approach: Dynamically constructs a SOQL query string by concatenating name.noQuotes() into the query, then executes it using Database.query().

Security: The noQuotes() method is not a standard Apex method on the String class. The Apex Developer Guide does not define noQuotes() as a built-in method (Salesforce Apex Developer Guide, String Class). Assuming it’s a custom method, it likely attempts to remove quotes from the string, but this does not prevent SOQL injection. Concatenating user input directly into the query string is inherently unsafe unless properly sanitized.

Example: If name = 'Test' OR '1'='1, and assuming noQuotes() does nothing (or removes quotes, which doesn’t help), the query becomes:

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SELECT Id FROM Account WHERE Name LIKE '%Test' OR '1'='1%'

The OR '1'='1' condition evaluates to true for all records, returning all Accounts, which is a successful SOQL injection attack.

Conclusion: Not safe, as it directly concatenates user input without proper sanitization or bind variables, and noQuotes() is not a reliable or standard method for preventing injection.

C.

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String query = 'SELECT Id FROM Account WHERE Name LIKE \'%' + String.escapeSingleQuotes(name) + '%\'';

List results = Database.query(query);

Approach: Dynamically constructs a SOQL query string by concatenating name into the query after applying String.escapeSingleQuotes(), then executes it using Database.query().

Security: The String.escapeSingleQuotes() method escapes single quotes in the input by adding a backslash (\), preventing the input from breaking out of the string literal in the SOQL query. The Apex Developer Guide states: “String.escapeSingleQuotes() prevents SOQL injection in dynamic queries by escaping single quotes, ensuring the input cannot alter the query structure” (Salesforce Apex Developer Guide, String Class). This ensures that even malicious input cannot manipulate the query logic.

Example: If name = 'Test' OR '1'='1, then String.escapeSingleQuotes(name) returns Test\' OR \'1\'=\'1. The query becomes:

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SELECT Id FROM Account WHERE Name LIKE '%Test\' OR \'1\'=\'1%'

This searches for records where Name matches the literal string %Test' OR '1'='1%, which is safe and does not allow the OR condition to execute as logic.

Conclusion: Safe from SOQL injection due to the use of String.escapeSingleQuotes() to sanitize the user input in a dynamic query.

D.

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String query = 'SELECT Id FROM Account WHERE Name LIKE \'%' + name + '%\'';

List results = Database.query(query);

Approach: Dynamically constructs a SOQL query string by directly concatenating name into the query, then executes it using Database.query().

Security: This approach is vulnerable to SOQL injection because name is directly embedded into the query string without sanitization. The Salesforce Secure Coding Guidelines warn: “Directly concatenating user input into a dynamic SOQL query without escaping can lead to SOQL injection” (Salesforce Secure Coding Guidelines, SOQL Injection).

Example: If name = 'Test' OR '1'='1, the query becomes:

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SELECT Id FROM Account WHERE Name LIKE '%Test' OR '1'='1%'

The OR '1'='1' condition evaluates to true for all records, returning all Accounts, demonstrating a successful SOQL injection attack.

Conclusion: Not safe, as it directly concatenates user input without sanitization or bind variables.

Why Options A and C are Correct:

Option A: Uses a bind variable (:query) in the SOQL query, ensuring that the user input (name) is treated as a literal value, not executable code. This is the most secure way to prevent SOQL injection, as recommended by Salesforce.

Option C: Uses String.escapeSingleQuotes() to sanitize the user input before embedding it into a dynamic SOQL query, preventing the input from altering the query’s logic. This is a safe approach for dynamic queries when bind variables cannot be used directly.

Options B and D: Both concatenate user input directly into the query string without adequate sanitization (noQuotes() is not a standard or reliable method in B, and D has no sanitization), making them vulnerable to SOQL injection.

Example of Vulnerability (Option D):

Consider a Visualforce page where name is set via a user input field:

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String name = ApexPages.currentPage().getParameters().get('name');

String query = 'SELECT Id FROM Account WHERE Name LIKE \'%' + name + '%\'';

List results = Database.query(query);

If a malicious user submits name = ' OR '1'='1, the query becomes:

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SELECT Id FROM Account WHERE Name LIKE '%' OR '1'='1%'

This returns all Accounts, bypassing the intended filtering, which is a successful SOQL injection attack.

Mitigating SOQL Injection:

Preferred (Option A): Use bind variables whenever possible:

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String query = '%' + name + '%';

List results = [SELECT Id FROM Account WHERE Name LIKE :query];

Alternative (Option C): If dynamic SOQL is required, sanitize input with String.escapeSingleQuotes():

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String query = 'SELECT Id FROM Account WHERE Name LIKE \'%' + String.escapeSingleQuotes(name) + '%\'';

List results = Database.query(query);

Handling Typos:

The options are syntactically correct in the provided image, with no typos to address.

Option B’s name.noQuotes() is not a standard Apex method, but the analysis assumes it’s a custom method that fails to prevent injection, as it’s not a recognized sanitization technique.

A. 75% Test Coverage:Salesforce mandates that 75% of all Apex code must be covered by tests to be deployable to production.

D. Trigger Coverage:Each Apex trigger must have at least one line of test coverage to ensure it is properly tested.

Using a formula field is the most efficient solution to calculate the ratio between rejected and approved timesheets. It minimizes maintenance overhead by dynamically calculating the value based on the existing roll-up summary fields.

Example Formula:

Total_Rejected_Timesheets__c / Total_Approved_Timesheets__c

Database.insert(records, false):

The Database.insert() method with the allOrNone parameter set to false allows for partial success.

If some records in the list fail due to validation rules, triggers, or other errors, the method will still attempt to insert the remaining valid records.

The false parameter ensures that records that fail will not roll back the transaction for the others.

Why not the other options?

A. Database.insert(records, true):

The true parameter makes the operation transactional (all or none). If any record fails, all records will roll back.

B. insert records:

The insert DML statement behaves like Database.insert(records, true) by default and rolls back all records if any error occurs.

C. insert(records, false):

This syntax is invalid in Apex.

Lightning Web Components (LWCs) have access to a variety of resources in Salesforce. Below are the supported resources:

Static Resources (A):You can use static resources to reference JavaScript libraries, images, and other files needed in an LWC.

SOSL:

Designed for full-text searches, making it faster for unstructured or broad text searches across multiple objects.

Ideal for searching multiple fields simultaneously.

SOQL:

Optimized for structured queries where you need more control over filtering and relationships.

Can return up to 50,000 records in a single query, while SOSL returns only 2,000.

CandDare incorrect because SOSL is faster for text searches, not SOQL.

A Global Picklist Value Set allows the same set of picklist values to be shared across multiple objects, making maintenance easier and ensuring consistency.

Why not other options?

B: Alphabetical ordering does not ensure consistent value maintenance across objects.

C: Validation rules do not streamline picklist value maintenance.

D: Restricting picklist values helps ensure data integrity but does not streamline maintenance across objects.

Global Picklists Documentation

In Visualforce, data-binding requires getter and setter methods to access the attributes of a controller. Adding a getter method foractTypeensures that its value is retrieved properly.

Why Re-Parentable Master-Detail Field?

A master-detail relationship allows Line Items to roll up totals (e.g., calculate total amount) to the Order.

Setting the relationship asre-parentablesupports moving Line Items between different Orders.

Why Not Other Options?

B. Lookup field: Does not support roll-up summary fields for calculations.

C and D: Relationships in the opposite direction (Order to Line Item) do not support the required logic.

The@RestResourceannotation exposes an Apex class as a RESTful web service. TheurlMappingparameter defines the endpoint's URL.