$replaceOne
Reference group: String aggregation expressions
What it does
Replaces the first matching substring; matching is case-sensitive.
Syntax
{$replaceOne: { input, find, replacement }}
Use case
Replace one known token.
$replaceOne: practical example
{ $project: { clean: { $replaceOne: { input: "$phone", find: " ", replacement: "" } } } }💡 Explanation
Replaces the first matching substring; matching is case-sensitive.
When to use it
Replace one known token.
Key Takeaways
- Replaces the first matching substring; matching is case-sensitive.
- Typical use: Replace one known token.