MongoDB regex to display records whose first five letters are uppercase?


Let us first create a collection with documents −

> db.upperCaseFiveLetterDemo.insertOne({"StudentFullName":"JOHN Smith"});
{
   "acknowledged" : true,
   "insertedId" : ObjectId("5cd7edef1a844af18acdffb2")
}
> db.upperCaseFiveLetterDemo.insertOne({"StudentFullName":"SAM Williams"});
{
   "acknowledged" : true,
   "insertedId" : ObjectId("5cd7ee011a844af18acdffb3")
}
> db.upperCaseFiveLetterDemo.insertOne({"StudentFullName":"CAROL Taylor"});
{
   "acknowledged" : true,
   "insertedId" : ObjectId("5cd7ee101a844af18acdffb4")
}
> db.upperCaseFiveLetterDemo.insertOne({"StudentFullName":"Bob Taylor"});
{
   "acknowledged" : true,
   "insertedId" : ObjectId("5cd7ee351a844af18acdffb5")
}
> db.upperCaseFiveLetterDemo.insertOne({"StudentFullName":"DAVID Miller"});
{
   "acknowledged" : true,
   "insertedId" : ObjectId("5cd7ee451a844af18acdffb6")
}

Following is the query to display all documents from a collection with the help of find() method −

> db.upperCaseFiveLetterDemo.find().pretty();

This will produce the following output −

{
   "_id" : ObjectId("5cd7edef1a844af18acdffb2"),
   "StudentFullName" : "JOHN Smith"
}
{
   "_id" : ObjectId("5cd7ee011a844af18acdffb3"),
   "StudentFullName" : "SAM Williams"
}
{
   "_id" : ObjectId("5cd7ee101a844af18acdffb4"),
   "StudentFullName" : "CAROL Taylor"
}
{
   "_id" : ObjectId("5cd7ee351a844af18acdffb5"),
   "StudentFullName" : "Bob Taylor"
}
{
   "_id" : ObjectId("5cd7ee451a844af18acdffb6"),
   "StudentFullName" : "DAVID Miller"
}

Following is the query to get the count of the records whose first five letters are in uppercase −

> db.upperCaseFiveLetterDemo.find({StudentFullName : {$regex : /[A-Z]{5}/ } }).count();

This will produce the following output −

2

There are two documents with first five letters uppercase. Let us now display those documents −

> db.upperCaseFiveLetterDemo.find({StudentFullName : {$regex : /[A-Z]{5}/ } });

This will produce the following output −

{ "_id" : ObjectId("5cd7ee101a844af18acdffb4"), "StudentFullName" : "CAROL Taylor" }
{ "_id" : ObjectId("5cd7ee451a844af18acdffb6"), "StudentFullName" : "DAVID Miller" }
raja
Published on 13-Jun-2019 12:32:50
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