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MongoDB equivalent of SELECT field AS `anothername`?
In MySQL, we give an alias name for a column. Similarly, you can give an alias name for field name in MongoDB. The MongoDB equivalent syntax is as follows
db.yourCollectionName.aggregate(
[
{ "$project": {
"_id": 0,
"anyAliasName": "$yourFieldName"
}}
]);Let us first create a collection with documents
> db.selectFieldAsAnotherNameDemo.insertOne({"Name":"Larry"});
{
"acknowledged" : true,
"insertedId" : ObjectId("5c9d448827b86948e204ca91")
}
> db.selectFieldAsAnotherNameDemo.insertOne({"Name":"Robert"});
{
"acknowledged" : true,
"insertedId" : ObjectId("5c9d449027b86948e204ca92")
}
> db.selectFieldAsAnotherNameDemo.insertOne({"Name":"Sam"});
{
"acknowledged" : true,
"insertedId" : ObjectId("5c9d449527b86948e204ca93")
}
> db.selectFieldAsAnotherNameDemo.insertOne({"Name":"Mike"});
{
"acknowledged" : true,
"insertedId" : ObjectId("5c9d449927b86948e204ca94")
}Following is the query to display all documents from a collection with the help of find() method
> db.selectFieldAsAnotherNameDemo.find().pretty();
This will produce the following output
{ "_id" : ObjectId("5c9d448827b86948e204ca91"), "Name" : "Larry" }
{ "_id" : ObjectId("5c9d449027b86948e204ca92"), "Name" : "Robert" }
{ "_id" : ObjectId("5c9d449527b86948e204ca93"), "Name" : "Sam" }
{ "_id" : ObjectId("5c9d449927b86948e204ca94"), "Name" : "Mike" }Following is the query for MongoDB equivalent of SELECT field AS `anothername`
> db.selectFieldAsAnotherNameDemo.aggregate(
... [
... { "$project": {
... "_id": 0,
... "StudentName": "$Name"
... }}
... ]);This will produce the following output
{ "StudentName" : "Larry" }
{ "StudentName" : "Robert" }
{ "StudentName" : "Sam" }
{ "StudentName" : "Mike" }
Updated on: 30-Jul-2019
2K+ Views
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