I want to write an $in query if column path starts with "/v1/user/1" or "/v1/user/2" then I want to select that particular document.
The sample document is as below:
{
"_id" : ObjectId("5f8872b486aa9e79d71d9809"),
"method" : "get",
"path" : "/v1/user/1/details/"
}
I tried to create a query but getting syntax error because of "/"
db.user.find({ "path": { $in: [ /^/v1/user/1/ , /^/v1/user/2/ ] } })
Could some one please help how to write the query.
Your query was almost correct. You just missed to escape the /. Try below query.
db.user.find({ "path": { $in: [ /^\/v1\/user\/1/ , /^\/v1\/user\/2/ ] } })
Related
I needed some help with the atlas search aggregation query.
I want to use $search syntax while doing the atlas search :
I have one collection; inside which I have one array field of ObjectIds like so :
arrayFieldOfObjectIds : [ObjectId(62ff26c349a3c47656765434), ObjectId(62ff26c349a3c47656765435)]
Now the array fields can also be empty in some cases like so :
arrayFieldOfObjectIds : []
I have defined the correct index mapping for this field.
My goal is to get all the documents that met the below conditions:
1. Either arrayFieldOfObjectIds doesn't exist.
2. If arrayFieldOfObjectIds does exist, it must be empty.
3. If arrayFieldOfObjectIds does exist, it must be equal to some specified value.
The query I have for arrayFieldOfObjectIds is :
{
"compound": {
"should": [
{
"compound": {
"mustNot": [
{
"exists": {
"path": "arrayFieldOfObjectIds1"
}
}
]
}
},
{
"equals": {
"value": ObjectId("62ff26c349a3c47656765434"),
"path": "arrayFieldOfObjectIds1"
}
}
],
"minimumShouldMatch": 1
}
}
This query doesn't give me those documents where arrayFieldOfObjectIds does exist and is empty.
Note: I need to use $search syntax and I also don't want to combine $match with $search as it kills the query performance altogether.
Thanks in advance.
Given collection:
{
"_id" : "1.1000038",
"recomendation" : [
"1.6739718"
]
}
/* 2 */
{
"_id" : "1.1000069",
"recomendation" : [
"1.9185509",
"1.9051998",
"1.9034279",
"1.8288046",
"1.8152670",
"1.858775",
"1.6224229",
"1.4591674",
"1.3862464",
"1.3427739",
"1.3080062",
"1.3003608",
"1.1694619",
"1.1634683",
"1.1590664",
"1.1524146",
"1.754599",
"1.700837",
"1.763617"
]
}
I need to query the MongoDB for a list of values and get the first element of the list of values
here is the query by mongo syntax
db.getCollection('similar_articles').find({"_id":{$in:["1.1000069","1.1000038"]}})
I don't want to filter it on the python side because it's can be too big.
I didn't find any documentation on it
desire output:
Pandas DataFrame
_id recom
1.1000038 1.6739718
1.1000069 1.9185509
I don't know pymongo so well, but you need this query:
First $match by _ids into the arreay (this is like the find you have).
And later use $project to create the field recom (you can use "recomendation" to overwrite the existing field) and set the value as the first into the array.
db.collection.aggregate([
{
"$match": { "_id": { "$in": [ "1.1000069", "1.1000038" ] } }
},
{
"$project": { "recom": { "$arrayElemAt": [ "$recomendation", 0 ] } }
}
])
Example here
Looking the doumentation it seems you only need to copy and paste this query.
An example document looks like this
{
"_id":ObjectId("562e7c594c12942f08fe4192"),
"Type": "f",
"runTime": ISODate("2016-12-21T13:34:00.000+0000"),
"data" : {
"PRICES SPOT" : [
{
"value" : 29.64,
"timeStamp" : ISODate("2016-12-21T23:00:00.000+0000")
},
{
"value" : 29.24,
"timeStamp" : ISODate("2016-12-22T00:00:00.000+0000")
},
{
"value" : 29.81,
"timeStamp" : ISODate("2016-12-22T01:00:00.000+0000")
},
{
"value" : 30.2,
"timeStamp" : ISODate("2016-12-22T02:00:00.000+0000")
},
{
"value" : 29.55,
"timeStamp" : ISODate("2016-12-22T03:00:00.000+0000")
}
]
}
}
My MongoDb has different Type of documents, I'd like to get a cursor for all of the documents that are from a time range that are of type: "f" but that actually exist. There are some documents in the database that broke the code I had previously(which did not check if PRICES SPOT existed).
I saw that I can use $and and $exists from the documentation. However, I am having trouble setting it up because of the range, and the nesting. I am using pyMongo as my python driver and also noticed here that I have to wrap the $and and $exists in quotes.
My code
def grab_forecast_cursor(self, model_dt_from, model_dt_till):
# create cursor with all items that actually exist
cursor = self._collection.find(
{
"$and":[
{'Type': 'f', 'runTime': {"$gte": model_dt_from, "$lte": model_dt_till}
['data']['PRICES SPOT': "$exists": true]}
]})
return cursor
This results in a Key Error it cannot find data. A sample document that has no PRICE SPOT looks exactly like the one I posted in the beginning, just without that respectively.
In short.. Can someone help me set up a query in which I can grab a cursor with all the documents of a certain type but that actually have respected contents nested in.
Update
I added a comma after the model_dt_till and have now a syntax error.
def grab_forecast_cursor(self, model_dt_from, model_dt_till):
# create cursor with all items that actually exist
cursor = self._collection.find(
{
"$and":[
{'Type': 'f', 'runTime': {"$gte": model_dt_from, "$lte": model_dt_till},
['data']['PRICES SPOT': "$exists": true]}
]})
return cursor
You're trying to use Python syntax to denote the path to a data structure, but the "database" want's it's syntax for the "key" using "dot notation":
cursor = self._collection.find({
"Type": "f",
"runTime": { "$gte": model_dt_from, "$lte": model_dt_till },
"data.PRICES SPOT.0": { "$exists": True }
})
You also don't need to write $and like that as ALL MongoDB query conditions are already AND expressions, and part of your statement was actually doing that anyway, so make it consistent.
Also the check for a "non-empty" array is 'data.PRICES SPOT.0' with the added bonus that not only do you know it "exists", but also that it has at least one item to process within it
Python and JavaScript are almost identical in terms of object/dict construction, so you really should be able to just follow the general documentation and the many samples here that are predominantly JavaScript.
I personally even try to notate answers here with valid JSON, so it could be picked up and "parsed" by users of any language. But here, python is just identical to what you could enter into the mongo shell. Except for True of course.
See "Dot Notation" for an overview of the syntax with more information at Query on Embedded / Nested Documents
I don't understand the behaviour of the command $exists.
I have two simple documents in the collection 'user':
/* 1 */
{
"_id" : ObjectId("59788c2f6be212c210c73233"),
"user" : "google"
}
/* 2 */
{
"_id" : ObjectId("597899a80915995e50528a99"),
"user" : "werty",
"extra" : "very important"
}
I want to retrieve documents which contain the field "extra" and the value is not equal to 'unimportant':
The query:
db.getCollection('users').find(
{"extra":{$exists:true},"extra": {$ne:"unimportant"}}
)
returns both two documents.
Also the query
db.getCollection('users').find(
{"extra":{$exists:false},"extra": {$ne:"unimportant"}}
)
returns both two documents.
It seems that $exists (when used with another condition on the same field) works like an 'OR'.
What I'm doing wrong? Any help appreciated.
I used mongodb 3.2.6 and 3.4.9
I have seen Mongo $exists query does not return correct documents
but i haven't sparse indexes.
Per MongoDB documentation (https://docs.mongodb.com/manual/reference/operator/query/and/):
Using an explicit AND with the $and operator is necessary when the same field or operator has to be specified in multiple expressions.
Therefore, and in order to enforce the cumpliment of both clauses, you should use the $and operator like follows:
db.getCollection('users').find({ $and : [ { "extra": { $exists : true } }, { "extra" : { $ne : "unimportant" } } ] });
The way you constructed your query is wrong, nothing to do with how $exists works. Because you are checking two conditions, you would need a query that does a logical AND operation to satisfy the two conditions.
The correct syntax for the query
I want to retrieve documents which contain the field "extra" and the
value is not equal to 'unimportant'
should follow:
db.getCollection('users').find(
{
"extra": {
"$exists": true,
"$ne": "unimportant"
}
}
)
or using the $and operator as:
db.getCollection('users').find(
{
"$and": [
{ "extra": { "$exists": true } },
{ "extra": { "$ne": "unimportant" } }
]
}
)
Here is an example of a document from the collection I am querying
meteor:PRIMARY> db.research.findOne({_id: 'Z2zzA7dx6unkzKiSn'})
{
"_id" : "Z2zzA7dx6unkzKiSn",
"_userId" : "NtE3ANq2b2PbWSEqu",
"collaborators" : [
{
"userId" : "aTPzFad8DdFXxRrX4"
}
],
"name" : "new one",
"pending" : {
"collaborators" : [ ]
}
}
I want to find all documents within this collection with either _userId: 'aTPzFad8DdFXxRrX4' or from the collaborators array, userId: 'aTPzFad8DdFXxRrX4'
So I want to look though the collection and check if the _userId field is 'aTPzFad8DdFXxRrX4'. If not then check the collaborators array on the document and check if there is an object with userId: 'aTPzFad8DdFXxRrX4'.
Here is the query I am trying to use:
db.research.find({$or: [{_userId: 'aTPzFad8DdFXxRrX4'}, {collaborators: {$in: [{userId: 'aTPzFad8DdFXxRrX4'}]}}] })
It does not find the document and gives me a syntax error. What is my issue here? Thanks
The $in operator is basically a simplified version of $or but you really only have one argument here so you should not even need it. Use dot notation instead:
db.research.find({
'$or': [
{ '_userId': 'aTPzFad8DdFXxRrX4'},
{ 'collaborators.userId': 'aTPzFad8DdFXxRrX4'}
]
})
If you need more than one value then use $in:
db.research.find({
'$or': [
{ '_userId': 'aTPzFad8DdFXxRrX4'},
{ 'collaborators.userId': {
'$in': ['aTPzFad8DdFXxRrX4','aTPzFad8DdFXxRrX5']
}}
]
})