Atomic update to embedded array item

[Ash]

How can update an embedded array item using atomic update

e.g. posts -> comments

i would like to update a comment which has id of 2 by change the
comment name

[Michael Dirolf]

Use the positional ($) modifier. So something like:
update({"comments.id": 2}, {$set: {"comments.$.name": "foo"}})

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[Ash]

thanks,

can i do that particular update that will only affect a specific post?

[Michael Dirolf]

Yes. Add something to the query document to select the post you want to update.

[Ash]

thank you, it all works now :D