Remove all fields that are null

Question

How can I remove all fields that are null from all documents of a given collection?

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I have a collection of documents such as:

{
           


        

Answer 1

Like this question mentioned (mongodb query without field name):

Unfortunately, MongoDB does not support any method of querying all fields with a particular value.

So, you can either iterate the document (like Wizard's example) or do it in non-mongodb way.

If this is a JSON file, remove all the lines with null in sed might works:

sed '/null/d' ./mydata.json