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ActiveRecord Attributes – access using Strings, Symbols and Direct Access rails

ActiveRecord Attributes – access using Strings, Symbols and Direct Access rails ?


Attributes can be accessed from ActiveRecord in various ways including symbolised, stringified or direct access. Each type of access has it’s own advantages and disadvantages as we will see in this tutorial.
Sample Table for use case -

Suppose we have a table users in database.
Table Name: users
id     name     city
1     Abcd     NewYork
2     Efgh     PolaAnd

Suppose, we want to have record of user with id = 21. Then we can get the details of this record using rails as,

user_details = User.where('id = 1').first

Now we will see different types of access over the active record user_details
1. Direct Access

Let us say we want to access name attribute of user from the ActiveRecord user_details. This can be obtained using direct access as follows,

name = user_details.name
puts "Name of the User is #{name}"
=> Abcd

By this way, direct access obtain value of attribute from ActiveRecord
2. Symbolised Access

Let us say we want to access name attribute of user from ActiveRecord user_details. This can be obtained using symbolised access as follows,

name = user_details[:name]
puts "Name of the User is #{name}"
=> Abcd

By this way, symbolised access obtain value of attribute from ActiveRecord
3. Stringified Access

Let us say we want to access name attribute of user from ActiveRecord user_details. This can be obtained using stringified access as follows,

name = user_details[‘name']
puts "Name of the User is #{name}"
=> Abcd

By this way, stringified access obtain value of attribute from ActiveRecord
How Direct Access is Faster?

Direct access is faster than symbolised or stringified access to get the value of attribute from ActiveRecord. Benchmarking the performance of Direct Access versus symbolised access versus stringified access is given below,

Benchmark.realtime do
    10000.times{p.id}
end
=> 0.006823

Benchmark.realtime do
    10000.times{p[:id]}
end
=> 0.015745

Benchmark.realtime do
    10000.times{p['id]'}
end
=> 0.017554

Above benchmarking clearly shows that Direct Access of attribute from ActiveRecord is much faster than the Symbolised or Stringified access.

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