@wxn0brp/db

Predefined Find Options Quick Reference (Post Data-Matching Processing)

Description

These options are applied as part of a post-processing step after matching objects are found in the database (find stage) but before the data is returned to the client.
This process is designed to:

1. Reduce data transfer size by removing unnecessary fields or selecting only the required ones.
2. Customize results by transforming objects to meet specific requirements.

This optimization improves both performance and result usability, ensuring the client receives precisely the needed data in a compact form.

Execution Stack

1. transform
2. exclude
3. select

Operators

select

Selects only specific fields to include in the final object.

// Original Object
{
    name: "John Doe",
    email: "john@example.com",
    age: 30,
    status: "active"
}

// Find Options
{
    select: ["name", "email"]
}

// Result
{
    name: "John Doe",
    email: "john@example.com"
}

exclude

Excludes specific fields from the object, removing unwanted data.

// Original Object
{
    name: "John Doe",
    email: "john@example.com",
    age: 30,
    status: "active"
}

// Find Options
{
    exclude: ["name"]
}

// Result
{
    email: "john@example.com",
    age: 30,
    status: "active"
}

transform

Applies a custom updater function to modify the object.

// Original Object
{
    name: "John Doe",
    email: "john@example.com",
    age: 30,
    status: "active"
}

// Find Options
{
    transform: (doc) => {
        doc.name = doc.name.toUpperCase();
        return doc;
    }
}

// Result
{
    name: "JOHN DOE",
    email: "john@example.com",
    age: 30,
    status: "active"
}

Combined Example

Using all operators together to demonstrate the execution stack.

// Original Object
{
    name: "John Doe",
    email: "john@example.com",
    age: 30,
    status: "active"
}

// Find Options
{
    transform: (doc) => {
        doc.newField = "added";
        doc.status = "inactive";
        return doc;
    },
    exclude: ["email", "newField"],
    select: ["name", "status"]
}

// Execution Steps:
1. transform:
   {
       name: "John Doe",
       email: "john@example.com",
       age: 30,
       status: "inactive",
       newField: "added"
   }
2. exclude:
   {
       name: "John Doe",
       age: 30,
       status: "inactive"
   }
3. select:
   {
       name: "John Doe",
       status: "inactive"
   }

// Final Result:
{
    name: "John Doe",
    status: "inactive"
}

This structured flow ensures flexible and predictable results, making it a powerful tool for refining and manipulating data.