Mongo db : data uploaded using CSV has Null stored as String in Mongo document

Question

I tried uploading data into Mongodb using CSV from Mongodb Compass. In the CSV, some of the fields have Null values stored in them. But, after uploading those fields in Mongo, documents have "Null" stored as String. Is there a way to store Null fields from CSV with the type Null?

score 1 · Answer 1 · answered Dec 30 '20 at 08:56

1

You can correct easily later:

db.contacts.update({a:"Null"}, {$set: {a: null}},{multi:true} )

or you can remove those fields from the document:

db.contacts.update({a:"Null"}, {$unset: {a:1}},{multi:true} )

answered Dec 30 '20 at 08:56

R2D2

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I wanted a solution at the time of insertion itself. There are thousands of documents (which will grow later on), don't want to update using query. Though, if it's the only solution will proceed with this. – Avani Khabiya Dec 30 '20 at 12:26
unfortunately mongoimport has no option yet to understand that "Null" string from csv need to be interpreted as null ... – R2D2 Dec 30 '20 at 12:57

score 1 · Accepted Answer · answered Mar 11 '21 at 09:29

I couldn't find a solution to import the data with NULL values using CSV and have them stored with datatype NULL in Mongodb. Then I imported the same data using JSON and it worked!! Importing data using JSON makes it to interpret NULL as NULL datatype, not as string.

Mongo db : data uploaded using CSV has Null stored as String in Mongo document

2 Answers2