> ## Documentation Index > Fetch the complete documentation index at: https://forest-chore-open-api.mintlify.site/llms.txt > Use this file to discover all available pages before exploring further. # Smart Fields ### What is a Smart Field? A field that displays a computed value in your collection. A Smart Field is a column that displays processed-on-the-fly data. It can be as simple as concatenating attributes to make them human friendly, or more complex (e.g. total of orders). ### Creating a Smart Field On our Live Demo, the very simple Smart Field `fullname` is available on the `Customer` collection. ```ruby theme={null} class Forest::Customer include ForestLiana::Collection collection :Customer field :fullname, type: 'String' do "#{object.firstname} #{object.lastname}" end end ``` Very often, the business logic behind the Smart Field is more complex and must interact with the database. Here’s an example with the Smart Field `full_address` on the `Customer` collection. ```ruby theme={null} class Forest::Customer include ForestLiana::Collection collection :Customer field :full_address, type: 'String' do address = Address.find_by(customer_id: object.id) "#{address[:address_line_1]} #{address[:address_line_2]} #{address[:address_city]} #{address[:country]}" end end ``` On our Live Demo, the very simple Smart Field `fullname` is available on the `Customer` collection. Ensure the file app/forest/\_\_init\_\_.py exists and contains the import of the previous defined class : Very often, the business logic behind the Smart Field is more complex and must interact with the database. Here’s an example with the Smart Field `full_address` on the `Customer` collection. On our Live Demo, the very simple Smart Field `fullname` is available on the `Customer` model. Very often, the business logic behind the Smart Field is more complex and must interact with the database. Here’s an example with the Smart Field `full_address` on the `Customer` model. The collection name must be the same as the **model name**. ### Updating a Smart Field By default, your Smart Field is considered as read-only. If you want to update a Smart Field, you just need to write the logic to “unzip” the data. **Note that the set method should always return the object it’s working on**. In the example hereunder, the `user_params` is returned is returned including only the modified data. ```ruby theme={null} class Forest::Customer include ForestLiana::Collection collection :Customer set_fullname = lambda do |user_params, fullname| fullname = fullname.split user_params[:firstname] = fullname.first user_params[:lastname] = fullname.last # Returns a hash of the updated values you want to persist. user_params end field :fullname, type: 'String', set: set_fullname do "#{object.firstname} #{object.lastname}" end end ``` For security reasons, the `fullname` Smart field will remain **read-only**, even after you implement the `set` method. To edit it, disable read-only mode in the field settings. By default, your Smart Field is considered as read-only. If you want to update a Smart Field, you just need to write the logic to “unzip” the data. **Note that the `set` method should always return the object it’s working on**. In the example hereunder, the `customer` object is returned including only the modified data. ### Searching, Sorting and Filtering on a Smart Field To perform a search on a Smart Field, you also need to write the logic to “unzip” the data, then the search query which is specific to your zipping. In the example hereunder, the `firstname` and `lastname` are searched separately after having been unzipped. ```ruby theme={null} class Forest::Customer include ForestLiana::Collection ​ collection :Customer ​ search_fullname = lambda do |query, search| firstname, lastname = search.split ​ # Injects your new filter into the WHERE clause. query.where_clause.send(:predicates)[0] << " OR (firstname = '#{firstname}' AND lastname = '#{lastname}')" ​ query end ​ field :fullname, type: 'String', set: set_fullname, search: search_fullname do "#{object.firstname} #{object.lastname}" end end ``` #### Filtering This feature is only available on agents version **6.7+** (version **6.2+** for Rails). To perform a filter on a Smart Field, you need to write the filter query logic, which is specific to your use case. In the example hereunder, the `fullname` is filtered by checking conditions on the `firstname` and `lastname` depending on the filter operator selected. ```ruby theme={null} class Forest::Customer include ForestLiana::Collection collection :Customer filter_fullname = lambda do |condition, where| first_word = condition['value'] && condition['value'].split[0] second_word = condition['value'] && condition['value'].split[1] case condition['operator'] when 'equal' "firstname = '#{first_word}' AND lastname = '#{second_word}'" when 'ends_with' if second_word.nil? "lastname LIKE '%#{first_word}'" else "firstname LIKE '%#{first_word}' AND lastname = '#{second_word}'" end # ... And so on with the other operators not_equal, starts_with, etc. end end field :fullname, type: 'String', is_read_only: false, is_required: true, is_filterable: true, filter: filter_fullname do "#{object.firstname} #{object.lastname}" end end ``` Make sure you set the option `isFilterable: true` in the field definition of your code. Then, you will be able to toggle the "Filtering enabled" option in the browser, in your **Fields Settings**. #### Sorting **Sorting** on a Smart Field is not *natively supported* in Forest. However you can check out those guides: * [Sort by Smart field](/legacy/ruby-agent/reference-guide/smart-fields/smart-field-examples/sort-by-smart-field) * [Sort by Smart field that includes value from a belongsTo relationship](/legacy/ruby-agent/reference-guide/smart-fields/smart-field-examples/sort-by-smart-field-that-includes-value-from-a-belongsto-relationship) ### Available Field Options Here are the list of available options to customize your Smart Field: | Name | Type | Description | | ----------- | ---------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------- | | field | string | The name of your Smart Field. | | type | string | Type of your field. Can be `Boolean`, `Date`, `Json`,`Dateonly`, `Enum`, `File`, `Number, ['String']` or `String` . | | enums | array of strings | (optional) Required only for the `Enum` type. This is where you list all the possible values for your input field. | | description | string | (optional) Add a description to your field. | | reference | string | (optional) Configure the Smart Field as a [Smart Relationship](/legacy/ruby-agent/reference-guide/models/relationships/overview#what-is-a-smart-relationship). | | isReadOnly | boolean | (optional) If `true`, the Smart Field won’t be editable in the browser. Default is `true` if there’s no `set` option declared. | | isRequired | boolean | (optional) If true, your Smart Field will be set as required in the browser. Default is false. | You can define a widget for a smart field from the [settings of your collection](https://docs.forestadmin.com/user-guide/collections/customize-your-fields). ### Building Performant Smart Fields To optimize your smart field performance, we recommend using a mechanism of batching and caching data requests. Implement them using the DataLoader which is a generic utility to be used as part of your application's data fetching layer to provide a simplified and consistent API over various remote data sources. #### Smart field declaration ####