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How to query bindata by type in mongodb?


Asked by Ermias Hardin on Dec 08, 2021 MongoDB



MongoDB query for counting number of unique fields grouped by another field? MongoDB - Query embedded documents? MongoDB query to sort by the sum of specified object inside inner array? Group by dates in MongoDB? To query by type, use subtype () in MongoDB.
In fact,
Sometimes, you need to deal with highly unstructured data where data types are unpredictable. In this case, you need to use the $type operator. The $type is an element query operator that allows you to select documents where the value of a field is an instance of a specified BSON type.
Furthermore, MongoDB drivers usually convert UUIDs between their Binary database representation and the language specific UUID data type. Initially the encoding method was platform specific and wasn’t consistently implemented across different MongoDB drivers. An example UUID created and displayed in a Java application would be shown as follows:
Subsequently,
A value of -1 next to a field name specifies descending order. Here we sort the results by name in descending order: You can sort by multiple fields. Just separate each field by a comma. When you do this, the documents will be sorted by the first field specified, then the next, and so on.
Accordingly,
ObjectId ¶. In MongoDB, each document stored in a collection requires a unique _id field that acts as a primary key. If an inserted document omits the _id field, the MongoDB driver automatically generates an ObjectId for the _id field. This also applies to documents inserted through update operations with upsert: true.