Get direct descendants in materialized path in MongoDB using regex

Question

In MongoDB collection, I have materialized path tree model like:

",Books,Programming,Databases,NoSQL,"
",Books,Programming,Databases,SQL,"

For fetching all descendants of Programming used:

db.categories.find( { path: /,Programming,/ } )

Is any availability to create request that will find only direct descendants Programming? I.e. will find records with Databases but not with NoSQL and SQL.

Answer 1

Use

/,Programming,[^,]+,$/

The [^,]+, pattern matches 1 or more symbols other than a comma ([^,]+) and the , matches a literal comma. $ is the end-of-string anchor.