How many separate queries when using populate()

[vresetnikov]

Hello,

When using the mongoose's populate() function, how many separate queries are fired?

I am asking this because having MongoDB on a separate instance I would like to cut the amount of roundtrips needed for the data to reduce the latency.

[vkarpov15]

1 per populated field by default. Unless you use cursors or perDocumentLimit. So, for example, await User.find().populate('friends').populate('blogPosts'), that executes 3 queries: 1 for users, 1 for friends, 1 for blog posts.