Complex MongoDB query with multiple OR - mongodb

I'm using mongodb and I've built to make the following query.
1 AccessToken.where('resource_owner_id').equals(event.resource_owner_id)
2 .where('revoked_at').equals(undefined)
3 .or([ { scopes: /resources/i }, { scopes: new RegExp(event.resource,'i') } ])
4 .or([ { device_ids: [] }, { device_ids: event.body.id } ])
For this example I'm using Mongoose and coffescript.
Unluckily it doesn't work as I want, mainly for the or statement. What I want is the two or on row 3 and 4 being independent.
This means that the field scopes (row 3) must contain the string resources or the string stored in event.resource, meanwhile the field device_ids must be empty or contain the id event.body.id.
From the tests I've prepared I can see that the or command put all together. This means that when just one of the four or conditions is satisfied I get the document.
- { scopes: /resources/i }
- { scopes: new RegExp(event.resource,'i') }
- { device_ids: [] }
- { device_ids: event.body.id }
What I'm not able to reach is to split them in two groups so that both the conditions related to the field scopes and the conditions related to the field device_ids can be satisfied.
Hope the problem is well described.
Thanks.

Don't use $where unless you absolutely have to as performance is terrible. Use a combination of the $or and $size operators instead:
UPDATE There's no Mongoose and method so you have to use the $and operator directly.
AccessToken.find({
resource_owner_id: event.resource_owner_id,
revoked_at: undefined,
$and: [
{ $or: [{ scopes: /resources/i }, { scopes: new RegExp(event.resource,'i') }] },
{ $or: [{ device_ids: { $size: 0 } }, { device_ids: event.body.id }] }
]
}, callback);

Related

Upserting nested fields with a dot(.) in key in MongoDB

I have query in MongoDB for which I'm trying to upsert an inner nested attribute that contains a dot(.) in the key. E.g. a document might look something like: (below is a fictitious example just to highlight the constraint I'm facing.)
const person = {
name: 'Peter',
address: {
'NY.postalCode': 12345,
'CA.postalCode': 23456,
}
}
However, when I try to update one of the nested attribute in address with the below $set operation, I get an additional object NY under address and its subKey postalCode as a result, instead of the flattened attribute within address.
await Person.findByIdAndUpdate(id, {
$set: {
'address.NY.postalCode': 98765,
}
}, { new: true });
// Output
{
name: 'Peter',
address: {
'NY.postalCode': 12345,
'CA.postalCode': 23456,
NY: {
postalCode: 98765,
}
}
}
I've tried using the escape character for dot (\u002e), but get the same output. Also, I have seen some new features for setting fields but only in Mongo v5: https://www.mongodb.com/docs/manual/reference/operator/aggregation/setField/#mongodb-expression-exp.-setField. However, we're using Mongo v4.2 and would not be able to upgrade until a while later.
Would like to check if there are any means to $set nested attributes in address that don't completely replace the address object? i.e. to be able to specifically upsert an inner attribute within address object?
For example, is it possible to use the aggregation framework to workaround this?
I've tried something like the below, but it didn't work - not sure if its something that I did wrong or its probably not possible to use the aggregation pipeline..
Person.aggregate([
{
$match: {
_id: id,
},
},
{
$replaceRoot: { newRoot: {
$mergeObjects: [
'$$ROOT.address',
{
'NY.postalCode': 98765,
},
],
} },
},
]);
For your scenario, you need to achieve the update with aggregation pipeline.
Use $literal to escape the field name with dot.
Via $mergeObjects to merge current address object with { NY.postalCode': 98765 }.
db.collection.update({
"_id": ObjectId("5a934e000102030405000000")
},
[
{
$set: {
"address": {
$mergeObjects: [
"$address",
{
$literal: {
"NY.postalCode": 98765
}
}
]
}
}
}
],
{
new: true
})
Demo # Mongo Playground

Appending a string to all values in an array field in MongoDB

I have a collection filled with docs that contain an "ip_addresses" field, which is an array of strings (IPs). I want to append '/32' to all of these values in all of my docs that don't already have a CIDR range suffix.
Here's my issue:
I don't know how to use the current value of the IP which is being iterated on.
Even if I did, $concat doesn't seem to work and throws an error even with placeholder values (as in the query below) - The dollar ($) prefixed field '$concat' in 'ip_addresses.0.$concat' is not valid for storage.
Here is my current query which throws the error:
db.getCollection('docs').update(
{},
{ $set: { "ip_addresses.$[ip]": { "$concat": [ "1.1.1.1", "/32" ] } } },
{
arrayFilters: [ { "ip": { $not: /.+\/\d{1,2}/ } } ],
multi: true
}
)
I'd appreciate help using the current values in the array in the $concat command and resolving the error.
Let's tackle each of the problems.
2 - $concat is an aggregation operator, hence it cannot be used for an update. you can view the list of available operators for an update here. You might notice that none of these "work" on actual document values which brings me back to the first question you had.
1 - In order you use a current document values within an update you have to use pipelined updates which is only available for Mongo v4.2+, if you're using a lesser Mongo version you have to fetch the documents into memory and do the update one by one in code. If you are on Mongo v4.2+ then the pipeline update syntax goes like this:
db.collection.updateMany(
{ip_addresses: {$exists: true}},
[
{
$set: {
ip_addresses: {
$map: {
input: '$ip_addresses',
as: 'ipAddress',
in: {
$cond: [
{
$regexMatch: {input: "$$ipAddress", regex: /.+\/\d{1,2}/}
},
'$$ipAddress',
{
$concat: [
'$$ipAddress',
'/32'
]
}
]
}
}
}
}
}
]
);

Mongo filter documents by array of objects

I have to filter candidate documents by an array of objects.
In the documents I have the following fields:
skills = [
{ _id: 'blablabla', skill: 'Angular', level: 3 },
{ _id: 'blablabla', skill: 'React', level: 2 },
{ _id: 'blablabla', skill: 'Vue', level: 4 },
];
When I make the request I get other array of skills, for example:
skills = [
{ skill: 'React', level: 2 },
];
So I need to build a query to get the documents that contains this skill and a greater or equal level.
I try doing the following:
const conditions = {
$elemMatch: {
skill: { $in: skills.map(item => item.skill) },
level: { $gte: { $in: skills.map(item => item.level) } }
}
};
Candidate.find(conditions)...
The first one seems like works but the second one doesn't work.
Any idea?
Thank you in advance!
There are so many problems with this query...
First of all item.tech - it had to be item.skill.
Next, $gte ... $in makes very little sense. $gte means >=, greater or equal than something. If you compare numbers, the "something" must be a number. Like 3 >= 5 resolves to false, and 3 >= 1 resolves to true. 3 >= [1,2,3,4,5] makes no sense since it resolves to true to the first 3 elements, and to false to the last 2.
Finally, $elemMatch doesn't work this way. It tests each element of the array for all conditions to match. What you was trying to write was like : find a document where skills array has a subdocument with skill matching at least one of [array of skills] and level is greater than ... something. Even if the $gte condition was correct, the combination of $elementMatch and $in inside doesen't do any better than regular $in:
{
skill: { $in: skills.map(item => item.tech) },
level: { $gte: ??? }
}
If you want to find candidates with tech skills of particular level or higher, it should be $or condition for each skill-level pair:
const conditions = {$or:
skills.map(s=>(
{skill: { $elemMatch: {
skill:s.skill,
level:{ $gte:s.level }
} } }
))
};

Pull and addtoset at the same time with mongo

I have a collection which elements can be simplified to this:
{tags : [1, 5, 8]}
where there would be at least one element in array and all of them should be different. I want to substitute one tag for another and I thought that there would not be a problem. So I came up with the following query:
db.colll.update({
tags : 1
},{
$pull: { tags: 1 },
$addToSet: { tags: 2 }
}, {
multi: true
})
Cool, so it will find all elements which has a tag that I do not need (1), remove it and add another (2) if it is not there already. The problem is that I get an error:
"Cannot update 'tags' and 'tags' at the same time"
Which basically means that I can not do pull and addtoset at the same time. Is there any other way I can do this?
Of course I can memorize all the IDs of the elements and then remove tag and add in separate queries, but this does not sound nice.
The error is pretty much what it means as you cannot act on two things of the same "path" in the same update operation. The two operators you are using do not process sequentially as you might think they do.
You can do this with as "sequential" as you can possibly get with the "bulk" operations API or other form of "bulk" update though. Within reason of course, and also in reverse:
var bulk = db.coll.initializeOrderedBulkOp();
bulk.find({ "tags": 1 }).updateOne({ "$addToSet": { "tags": 2 } });
bulk.find({ "tags": 1 }).updateOne({ "$pull": { "tags": 1 } });
bulk.execute();
Not a guarantee that nothing else will try to modify,but it is as close as you will currently get.
Also see the raw "update" command with multiple documents.
If you're removing and adding at the same time, you may be modeling a 'map', instead of a 'set'. If so, an object may be less work than an array.
Instead of data as an array:
{ _id: 'myobjectwithdata',
data: [{ id: 'data1', important: 'stuff'},
{ id: 'data2', important: 'more'}]
}
Use data as an object:
{ _id: 'myobjectwithdata',
data: { data1: { important: 'stuff'},
data2: { important: 'more'} }
}
The one-command update is then:
db.coll.update(
'myobjectwithdata',
{ $set: { 'data.data1': { important: 'treasure' } }
);
Hard brain working for this answer done here and here.
Starting in Mongo 4.4, the $function aggregation operator allows applying a custom javascript function to implement behaviour not supported by the MongoDB Query Language.
And coupled with improvements made to db.collection.update() in Mongo 4.2 that can accept an aggregation pipeline, allowing the update of a field based on its own value,
We can manipulate and update an array in ways the language doesn't easily permit:
// { "tags" : [ 1, 5, 8 ] }
db.collection.updateMany(
{ tags: 1 },
[{ $set:
{ "tags":
{ $function: {
body: function(tags) { tags.push(2); return tags.filter(x => x != 1); },
args: ["$tags"],
lang: "js"
}}
}
}]
)
// { "tags" : [ 5, 8, 2 ] }
$function takes 3 parameters:
body, which is the function to apply, whose parameter is the array to modify. The function here simply consists in pushing 2 to the array and filtering out 1.
args, which contains the fields from the record that the body function takes as parameter. In our case, "$tag".
lang, which is the language in which the body function is written. Only js is currently available.
In case you need replace one value in an array to another check this answer:
Replace array value using arrayFilters

Optimized way of Querying in MongoDB using $in vs $or

Implementing an application that looks up a table for mail id presence from a list of around 10 email ids. Tried using $or and $in.
$in seems to give better performance but not significant. Is one more optimized than other?
MongoDB docs have the answer:
"When using $or with <expressions> that are equality checks for the value of the same field, choose the $in operator over the $or operator."
$or operator is logical operator where you can define your own login but $in operator is Comparison operator where you can compare you can not put your on logic.
Syntax of $in:
{ field: { $in: [<value1>, <value2>, ... <valueN> ] } }
Example:
db.account.find( { qty: { $in: [ 5, 15 ] } } )
Syntax of $or:
{ $or: [ { <expression1> }, { <expression2> }, ... , { <expressionN> } ] }
Example:
db.account.find( { $or: [ { quantity: { $lt: 20 } }, { price: 10 } ] } )
Note: Account is your collection name
"While "$or"will always work, use "$in"whenever possible as the query optimizer
handles it more efficiently."
Moreover "$in" has more readability.
Ref: MongoDB: The Definitive Guide
Well that will insure no indecis to be ensured if you use $in, however i prefer to format it to $or as it will ensure index (readability won't concern me at is being handled in application logic in which i prefer to consume the memory of app rather than mongodb server)