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MongoDB query for documents whose array elements does not have a specific value
For such cases, use $elemMatch. This operator matches documents that contain an array field with at least one element that matches all the specified query criteria.
Let us create a collection with documents −
> db.demo239.insertOne(
... {
... "Name" : "Chris",
... "details" : [
... { "DueDate" : new ISODate("2019-01-21"), "ProductPrice" : 1270 },
... { "DueDate" : new ISODate("2020-02-12"), "ProductPrice" : 2000 }
... ]
... }
...);
{
"acknowledged" : true,
"insertedId" : ObjectId("5e441c6bf4cebbeaebec5157")
}
> db.demo239.insertOne(
... {
... "Name" : "David",
... "details" : [
... { "DueDate" : new ISODate("2018-11-11"), "ProductPrice" : 1450},
... { "DueDate" : new ISODate("2020-02-12") }
... ]
... }
...);
{
"acknowledged" : true,
"insertedId" : ObjectId("5e441c6cf4cebbeaebec5158")
}
Display all documents from a collection with the help of find() method −
> db.demo239.find();
This will produce the following output −
{
"_id" : ObjectId("5e441c6bf4cebbeaebec5157"), "Name" : "Chris", "details" : [
{ "DueDate" : ISODate("2019-01-21T00:00:00Z"), "ProductPrice" : 1270 },
{ "DueDate" : ISODate("2020-02-12T00:00:00Z"), "ProductPrice" : 2000 }
]
}
{
"_id" : ObjectId("5e441c6cf4cebbeaebec5158"), "Name" : "David", "details" : [
{ "DueDate" : ISODate("2018-11-11T00:00:00Z"), "ProductPrice" : 1450 },
{ "DueDate" : ISODate("2020-02-12T00:00:00Z") }
]
}
Following is the query to fetch documents whose array elements does not have a specific value −
> db.demo239.find({ "details": { "$elemMatch": { "DueDate": { "$exists": true }, "ProductPrice": { "$exists": false } } } })
This will produce the following output −
{ "_id" : ObjectId("5e441c6cf4cebbeaebec5158"), "Name" : "David", "details" : [ { "DueDate" : ISODate("2018-11-11T00:00:00Z"), "ProductPrice" : 1450 }, { "DueDate" : ISODate("2020-02-12T00:00:00Z") } ] }Advertisements