Suppose i have a document like
{
"_id" : 5,
"rows": [
{ "id" : "aab", "value":100},
{ "id" : "aac", "value":400},
{ "id" : "abc", "value":200},
{ "id" : "xyz", "value":300}
]
}
and i need to add a new key in each sub document "status" : 1 and result should be look like
{
"_id" : 5,
"rows": [
{ "id" : "aab", "value":100, "status":1},
{ "id" : "aac", "value":400, "status":1},
{ "id" : "abc", "value":200, "status":1},
{ "id" : "xyz", "value":300, "status":1}
]
}
How can i do this by single update query?
Mongo positional operator with $elemMatch
having problem;
The $ operator can update the first array element that matches multiple query criteria specified with the $elemMatch() operator.
So this case using mongo query you should update only specific matching criteria. If you set rows.aac
in match then you will add status:1
in row.aac
array, check query as below :
db.collectionName.update({
"_id": 5,
"rows": {
"$elemMatch": {
"id": "abc"
}
}
}, {
$set: {
"rows.$.status": 1
}
}, true, false) // here you insert new field so upsert true
mongo update showing how upsert
and multi
works.
But still you want to updated all documents then you should use some programming code
or some script
. Below code update all data using cursor forEach :
db.collectionName.find().forEach(function(data) {
for (var ii = 0; ii < data.rows.length; ii++) {
db.collectionName.update({
"_id": data._id,
"rows.id": data.rows[ii].id
}, {
"$set": {
"rows.$.status": 1
}
}, true, false);
}
})
If your documents size more then better way to use mongo bulk update below code shows how to updated using mongo bulk :
var bulk = db.collectionName.initializeOrderedBulkOp();
var counter = 0;
db.collectionName.find().forEach(function(data) {
for (var ii = 0; ii < data.rows.length; ii++) {
var updatedDocument = {
"$set": {}
};
var setStatus = "rows." + ii + ".status";
updatedDocument["$set"][setStatus] = 101;
// queue the update
bulk.find({
"_id": data._id
}).update(updatedDocument);
counter++;
// re-initialize every 1000 update statements
if (counter % 1000 == 0) {
bulk.execute();
bulk = db.collectionName.initializeOrderedBulkOp();
}
}
});
// Add the rest in the queue
if (counter % 1000 != 0)
bulk.execute();
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With