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Get names of all keys in the MongoDB collection?
The syntax to get names of all keys in the collection is as follows:
var yourVariableName1=db.yourCollectionName.findOne();
for(var yourVariableName 2 in yourVariableName1) { print(yourVariableName); }To understand the above syntax, let us create a collection with documents. The collection name we are creating is “studentGetKeysDemo”.
The following is the query to create documents:
>db.studentGetKeysDemo.insert({"StudentId":1,"StudentName":"Larry","StudentAge":23,"StudentAddress":"US",
... "StudentHobby":["Cricket","Football","ReadingNovel"],
"StudentMathMarks":89,"StudentDOB":ISODate('1998-04-06')});The following is the output:
WriteResult({ "nInserted" : 1 })Display all documents from a collection with the help of find() method. The query is as follows:
> db.studentGetKeysDemo.find().pretty();
The following is the output:
{
"_id" : ObjectId("5c6c12dd68174aae23f5ef5f"),
"StudentId" : 1,
"StudentName" : "Larry",
"StudentAge" : 23,
"StudentAddress" : "US",
"StudentHobby" : [
"Cricket",
"Football",
"Reading Novel"
],
"StudentMathMarks" : 89,
"StudentDOB" : ISODate("1998-04-06T00:00:00Z")
}Here is the query to get names of all keys from the collection “studentGetKeysDemo”:
> var allKeys=db.studentGetKeysDemo.findOne();
> for(var myKey in allKeys){print(myKey);}The following is the output displaying all the keys:
_id StudentId StudentName StudentAge StudentAddress StudentHobby StudentMathMarks StudentDOB
Updated on: 30-Jul-2019
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