Memcached Get in Ruby (Detailed Guide w/ Code Examples)

Use Case(s)

The get method in Memcached is used to retrieve the value of a specified key from the Memcached server. This is commonly used when you want to fetch data that was previously stored in Memcached, such as session data, user preferences, or other data that may be expensive to compute or retrieve from a database.

Code Examples

Here's how you can use the get method with Memcached in Ruby:

require 'memcached'
cache = Memcached.new('localhost:11211')

# Store a value
cache.set('my_key', 'Hello, World!')

# Retrieve the value
value = cache.get('my_key')
puts value # Outputs: 'Hello, World!'

In this example, we're storing a string 'Hello, World!' under the key 'my_key', and then retrieving it using get.

If you try to get a key that does not exist, Memcached will raise a Memcached::NotFound error. You should handle this case appropriately in your code:

begin
  value = cache.get('non_existing_key')
rescue Memcached::NotFound => e
  puts "Key not found: #{e}"
end

In this example, if the key 'non_existing_key' does not exist, the code catches the exception and prints a message.

Best Practices

• Make sure to handle Memcached::NotFound exceptions when using get. It's better to handle these errors gracefully than to let them crash your program.
• Use meaningful and consistent key naming conventions so keys are easy to remember and retrieve.
• Avoid storing large objects in Memcached. It's intended for small, frequently-accessed pieces of data.

Common Mistakes

• Not handling Memcached::NotFound exceptions when using get.
• Storing large data in Memcached. It is not a persistent data store and should not be used as one.

FAQs

Q: What happens if I try to get a key that doesn't exist? A: If you try to get a key that doesn't exist in Memcached, it will raise a Memcached::NotFound exception.

Q: Can I store any type of data in Memcached with Ruby? A: Yes, you can store any data that can be serialized into a string format, including strings, numbers, arrays, and even some types of objects.