$set / $addFields
Reference group: Pipeline stages
What it does
Adds or overwrites fields; $addFields aliases $set.
Syntax
{$set: { field: expression }}
Use case
Create intermediate values.
$set / $addFields: practical example
{ $set: { fullName: { $concat: ["$firstName", " ", "$lastName"] } } }💡 Explanation
Adds or overwrites fields;
$addFields aliases $set.
When to use it
Create intermediate values.Key Takeaways
- Adds or overwrites fields;
$addFieldsaliases$set. - Typical use: Create intermediate values.