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data type converstion in DocumentDB using aggregation pipelines


I have a MongoDB aggregation pipeline that converts a string to a double. I just realized that DocumentDB doesn't support the $convert or $toDouble operators. Is there any workaround for this problem while still using an aggregation pipeline?

Below is an extract from my pipeline that works in MongoDB Atlas:

asked 6 months ago149 views
1 Answer

Hello. You could use the Javascript parseFloat() method and programmatically update those strings to double in the existing collection. Or use an $out stage in the aggregation and update the results afterwards. Something like this will loop through all documents in the collection and update the string:

db.collection.find({}).forEach( function(doc) {
  doc.subDoc.stringVar = parseFloat( doc.subDoc.stringVar );
  db.collection.update( { _id: doc._id }, {$set: { "subDoc.stringVar": doc.subDoc.stringVar } } )
answered 5 months ago

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