nimrod serok questions

nimrod serok answers

• How to find_one in mongodb if the key is not always present?
• Get count of returned documents in $lookup pipeline before $limit - MongoDB
• Mongodb - Find coupled documents, where A is following B and B is following A
• How to do operations to a document other than the current one in MongoDB's setWindowFields
• Mongodb sort Aggregation in same order ids was passed on filter
• How to make conditional projections based on sub-documents using MongoDB?
• How to find the hours difference between two dates in mongodb
• How to use MongoDB aggregation for pagination?