@George4792

A keyed data page is a type of data page in Pega that allows you to store and retrieve data based on a key-value pair. The key is used to uniquely identify the data, and the value is the actual data that you want to store.

When defining a keyed data page, you have the option to specify a user-defined key. This key is typically a property or a combination of properties that you define in your application. The user-defined key should be unique for each piece of data you want to store in the data page.

By using a user-defined key, you can retrieve specific data from the keyed data page by providing the key value. Pega internally uses the key to efficiently locate and retrieve the corresponding data from the data page.

For example, let's say you have a keyed data page that stores customer information, and you define a user-defined key using the customer ID property. You can then use this customer ID to retrieve the specific customer's data from the data page.

Using user-defined keys in keyed data pages allows for efficient data retrieval and caching, as Pega can quickly locate the data associated with a specific key without having to perform additional database queries or calculations.

It's important to choose a key that uniquely identifies the data you want to store and retrieve and ensures efficient lookup operations.

@George4792 , 

when you create a data page with list structure and read only mode then you see access pages with user defined keys. Keyed data page retrieves one record from the list of records. This can be done through look up too but look needs class key to fetch specific record, for keyed data page you can fetch with your own property by selecting the option access pages with user defined keys.  This allows us to create a single data page to retrieve  list and as well as single page record from SOR. Hope I have answered your questions