$switch
Reference group: Conditional and logical expressions
What it does
Returns the first matching branch result.
Syntax
{$switch: { branches: [{ case, then }], default }}
Use case
Multi-range classification.
$switch: practical example
{ $project: { band: { $switch: { branches: [{ case: { $lt: ["$score", 50] }, then: "low" }, { case: { $lt: ["$score", 80] }, then: "medium" }], default: "high" } } } }💡 Explanation
Returns the first matching branch result.
When to use it
Multi-range classification.
Key Takeaways
- Returns the first matching branch result.
- Typical use: Multi-range classification.