Deletes one or more keys and returns the number actually removed.
The objective is to understand the behavior and operational limits, not only the method name.
What It Does
Deletes one or more keys and returns the number actually removed.
Syntax and Return Value
Redis::del(...)
The return value and exceptional cases depend on the call described here: Deleting an absent key returns zero; avoid broad destructive key patterns.
Requirements: install and enable the corresponding PHP driver or extension and configure the service before running the examples.
Example 1: Basic Use
Requires the phpredis extension and a running Redis server. Keys use a guide-specific prefix; clean up example keys after experimenting.
<?php
$redis = new Redis();
$redis->connect(getenv('REDIS_HOST') ?: '127.0.0.1', (int) (getenv('REDIS_PORT') ?: 6379), 2.0);
$redis->set('guide:del:1','draft');
echo $redis->del('guide:del:1');
Example 2: A Second Scenario
Requires the phpredis extension and a running Redis server. Keys use a guide-specific prefix; clean up example keys after experimenting.
<?php
$redis = new Redis();
$redis->connect(getenv('REDIS_HOST') ?: '127.0.0.1', (int) (getenv('REDIS_PORT') ?: 6379), 2.0);
$redis->set('guide:del:2','review');
echo $redis->del('guide:del:2');
Example 3: Practical Checks
Requires the phpredis extension and a running Redis server. Keys use a guide-specific prefix; clean up example keys after experimenting.
<?php
$redis = new Redis();
$redis->connect(getenv('REDIS_HOST') ?: '127.0.0.1', (int) (getenv('REDIS_PORT') ?: 6379), 2.0);
$redis->set('guide:del:3','published');
echo $redis->del('guide:del:3');
Important Behavior and Edge Cases
Deleting an absent key returns zero; avoid broad destructive key patterns.
For production use, also account for error handling, data validation, resource limits and environment-specific driver behavior.
Comparison with Related Approaches
| Approach | Important distinction |
|---|---|
| Redis::del | Deletes one or more keys and returns the number actually removed. |
| Related API / pattern | expire sets a time limit without immediately removing the key. |
Common Beginner Mistakes
| Mistake | Correct approach |
|---|---|
| Assuming the happy path covers edge cases | Deleting an absent key returns zero; avoid broad destructive key patterns. |
| Using a related API interchangeably | expire sets a time limit without immediately removing the key. |
Key Takeaways
- Deletes one or more keys and returns the number actually removed.
- Deleting an absent key returns zero; avoid broad destructive key patterns.
- expire sets a time limit without immediately removing the key.
Choose this API or pattern when its exact semantics match your task, and verify the result against the database driver and runtime used by your application.