Reads several string keys in one command.
The objective is to understand the behavior and operational limits, not only the method name.
What It Does
Reads several string keys in one command.
Syntax and Return Value
Redis::mget(...)
The return value and exceptional cases depend on the call described here: Missing keys yield false entries by default; preserve the order of requested keys.
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);
$redis->mset(['guide:mget:1'=>'draft','guide:mget:1:secondary'=>"ready"]);
echo json_encode($redis->mget(['guide:mget:1','guide:mget:1:secondary',"no-such-key"]));
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);
$redis->mset(['guide:mget:2'=>'review','guide:mget:2:secondary'=>"ready"]);
echo json_encode($redis->mget(['guide:mget:2','guide:mget:2:secondary',"no-such-key"]));
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);
$redis->mset(['guide:mget:3'=>'published','guide:mget:3:secondary'=>"ready"]);
echo json_encode($redis->mget(['guide:mget:3','guide:mget:3:secondary',"no-such-key"]));
Important Behavior and Edge Cases
Missing keys yield false entries by default; preserve the order of requested keys.
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::mget | Reads several string keys in one command. |
| Related API / pattern | get reads one key per call. |
Common Beginner Mistakes
| Mistake | Correct approach |
|---|---|
| Assuming the happy path covers edge cases | Missing keys yield false entries by default; preserve the order of requested keys. |
| Using a related API interchangeably | get reads one key per call. |
Key Takeaways
- Reads several string keys in one command.
- Missing keys yield false entries by default; preserve the order of requested keys.
- get reads one key per call.
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.