MongoDB Aggregations: $cond in C#
When converting mongoDB $cond ( https://docs.mongodb.com/manual/reference/operator/aggregation/cond/ ) aggregation query some times it seems really complex to write in C#. MongoDB has provided 2 different ways to write $cond statement. 1st Approach: { $cond : { if : < boolean - expression > , then : < true - case > , else : < false - case -> } } or 2nd Approach: { $cond : [ < boolean - expression > , < true - case > , < false - case > ] } In order to reduce the complexity of $cond statement, it is always good to use the 2nd Approach , because it will reduce the number of BsonDocumnets which will require when writing the aggregation in C#. So in the following example, I have used a $redact ( https://docs.mongodb.com/manual/reference/operator/aggregation/redact/ ) which use to drop objects with a condition statement. So if a field in that object does not matched with a given value that object will dropped. MongoDB Aggre