❔ PHP Conditional Operators – Ternary & Null Coalescing Explained

🧲 Introduction – Why Conditional Operators Matter in PHP

In PHP, conditional operators — especially the ternary operator — are shorthand tools for writing concise if-else logic. They help simplify code readability by reducing multiple lines into one.

Instead of writing:

if ($age >= 18) {
  $status = "Adult";
} else {
  $status = "Minor";
}

You can write:

$status = ($age >= 18) ? "Adult" : "Minor";

🎯 In this guide, you’ll learn:

• What conditional (ternary) operators are
• Syntax and variations
• Practical examples with explanation
• Null coalescing operator (??)
• Best practices and common pitfalls

📘 What Are Conditional Operators in PHP?

PHP provides the following conditional operators:

🔀 Ternary Operator (?:) — Basic Syntax

(condition) ? true_expression : false_expression;

✅ Example:

$age = 20;
$status = ($age >= 18) ? "Adult" : "Minor";
echo $status;  // Output: Adult

📘 Explanation:

• The condition $age >= 18 is true
• So "Adult" is assigned to $status

🔁 Nested Ternary Operators

$score = 85;
$result = ($score >= 90) ? "A" : (($score >= 75) ? "B" : "C");
echo $result;  // Output: B

📘 Explanation:

• $score is 85, not ≥ 90 → skip “A”
• Then check $score >= 75 → it’s true → assign “B”

⚠️ Avoid overusing nested ternaries — they reduce readability.

🧪 Ternary Without Middle (PHP 5.3+)

PHP allows a shorthand ternary where only the true expression is written:

$username = $_GET['user'] ?: 'Guest';
echo $username;

📘 Explanation:
If $_GET['user'] exists and is not empty, use it; otherwise, use 'Guest'.

❓ Null Coalescing Operator (??) – PHP 7+

The ?? operator is used to check if a variable is set and not null. It’s better than using isset() manually.

✅ Example:

$username = $_GET['user'] ?? 'Guest';
echo $username;

📘 Explanation:
Returns 'Guest' if $_GET['user'] is not set or is null.

✅ Safer than:

$username = isset($_GET['user']) ? $_GET['user'] : 'Guest';

🧠 Best Practices

• ✅ Use ternary operator for short and simple conditions
• ✅ Use parentheses to group logic clearly
• ✅ Use ?? for default fallbacks (e.g., form values)
• ❌ Avoid deeply nested ternary chains
• ❌ Do not over-optimize — clarity matters

📌 Summary – Recap & Next Steps

PHP’s conditional (ternary) operators are powerful tools for writing compact conditions. While convenient, they should be used carefully to avoid sacrificing readability.

🔍 Key Takeaways:

• ?: is shorthand for if...else
• ?? handles isset() and null in one operator
• Use ternary for short decisions, not complex logic chains

⚙️ Real-World Relevance:
Used in setting defaults, inline conditional rendering, fallbacks, and quick logic assignments.

❓ Frequently Asked Questions (FAQs)

❓ What’s the difference between ?: and ?? in PHP?
✅ ?: checks truthiness, ?? checks if a variable is set and not null.

❓ Can I nest ternary operators in PHP?
✅ Yes, but avoid deeply nested ternaries to maintain readability.

❓ Is ?? faster than using isset() with ternary?
✅ Yes. It’s faster and more readable than combining isset() with ?:.

❓ When should I use ternary vs traditional if...else?
✅ Use ternary for short, inline decisions; use if...else for multiple statements.