I'm having group of array of element in MongoDB as given below :
{
"_id" : 5,
"quizzes" : [
{
"wk" : 1,
"score" : 10
},
{
"wk" : 2,
"score" : 8
},
{
"wk" : 3,
"score" : 5
}
],
"play" : [
{
"wk" : 2,
"score" : 8
},
{
"wk" : 3,
"score" : 5
}
]
}
I am trying insert new record in array if not present and if record present in that array then update that array record. Below is my MongoDB query.
db.push.update(
{ _id: 5 },
{ $push: { "quizzes": {"wk" : 6.0,"score" : 8.0},"play": {"wk" : 6.0,"score" : 8.0} } }
)
Every time when i execute this query it inserts new record in array but i want if record present then update that array.
Use $addToSet instead of $push.
db.push.update(
{ _id: 5 },
{ $addToSet: { "quizzes": {"wk": 6.0, "score": 8.0}, "play": {"wk": 6.0, "score": 8.0} } }
)
EDIT:
There is no simple built-in approach for conditional sub-document update in an array field, by specific property. However, a small trick can do the job by executing two commands in sequence.
For example: If we want to update the quizzes field with the object { "wk": 7.0, "score": 8.0 }, we can do it in two steps:
Step-1: $pull out sub-documents from the quizzes array where "wk": 7.0. (Nothing happens if matching sub-document not found).
db.push.update(
{ _id: 5 },
{ $pull: { "quizzes": { "wk": 7.0 } } }
)
Step-2: $addToSet the sub-document.
db.push.update(
{ _id: 5 },
{ $addToSet: { "quizzes": {"wk": 7.0, "score": 8.0} } }
)
You can combine the above two update commands using the bulk.find().update()
I assume what you want to do is, add a property to an element of the array based on the same element's different property's value.
You can use the updateOne() function with the $(update) operator, please refer the document mongodb documentation for $(update).
Let's say you want to add a property description to the array element where the value of wk is 1 (assuming its some kind of key based on what you have provided)
Input: Your data collection given in the question.
Mongo Command:
db.<your_collection_name>.updateOne(
{
"_id":5,
"quizzes.wk":1
},
{
$set:{
"quizzes.$.description":"I am a new property"
}
});
Output:
{
"_id" : 5,
"quizzes" : [
{
"wk" : 1,
"score" : 10,
"description" : "I am a new property"
},
{
"wk" : 2,
"score" : 8
},
{
"wk" : 3,
"score" : 5
}
],
"play" : [
{
"wk" : 2,
"score" : 8
},
{
"wk" : 3,
"score" : 5
}
]
}
Note: It will only change one entry of an array, the one which is matched first.