PHP Memcached Get (Detailed Guide w/ Code Examples)

Use Case(s)

The 'php memcached get' command is commonly used to fetch data that has been stored in the Memcached server. This is typically done in situations where you want to avoid expensive database queries by storing the result of a query in memory and fetching it when required.

Code Examples

Here are some examples of how to use 'php memcached get':

1. Basic usage:

$mem = new Memcached();
$mem->addServer("127.0.0.1", 11211);

$key = "some_key";
$value = $mem->get($key);

if ($value) {
    echo $value;
} else {
    echo "No data for key: " . $key;
}

This example connects to a Memcached server running on localhost and tries to get the value associated with 'some_key'. If the value exists, it will print the value; otherwise, it echoes that there's no data for this key.

2. Fetching multiple keys:

$mem = new Memcached();
$mem->addServer("127.0.0.1", 11211);

$keys = array("key1", "key2", "key3");
$values = $mem->getMulti($keys);

print_r($values);

In this example, we're fetching multiple values at once using 'getMulti'. This function returns an associative array with keys and their corresponding values.

Best Practices

1. Always check if the data exists before trying to use it. The 'get' method returns FALSE if the key does not exist.
2. Use 'getMulti' for fetching multiple keys at once instead of individual 'get' calls to reduce network overhead.

Common Mistakes

1. Not checking the existence of a key before trying to use the value, leading to unexpected behavior when 'FALSE' is returned.
2. Misjudging the lifetime of data stored in Memcached. Remember that Memcached is a caching solution and not a persistent store. It may evict data earlier than expected under memory pressure.

FAQs

1. What if the key doesn't exist? If the key does not exist, the 'get' function returns FALSE.

2. Can I fetch multiple keys at once? Yes, you can use the 'getMulti' function to fetch multiple keys at once.

3. Does 'get' update the expiration time? No, calling 'get' does not affect the expiration time of the cached item.