How to query all documents present inside an Array which itself is present in a MongoDB collection under Node.js.
For example: I have a DB with a structure:
{
"name1":[{"height":"5.5"},
{"weight":"57"}],
"name2":[{"height":"6.1"},
{"weight":"74"}]
}
What query should I make to get all the documents( i.e. height, weight) of the array "name1"
Output should be :
{
{ "height":"5.5"}
{"weight":"57"}
}
My suggestion would be to reorganise the collection so each document has a key of name and key of physicalattributes e.g.
{
'name' : 'name1',
'physAttr': ['height': heightvalue,
'weight': weightvalue]
}
then suppose you wanted to find all documents with height 5.5, the query would be trivial
db.collection.find({ 'physAttr.height': 5.5 })
As described in the question each document in the collection has a different schema from the others (different name key for every document) making query operations difficult.
Related
I have an index that returns something like this
Company_All {
name : string;
id : string;
agentDocumentId : string
}
is it possible to load the related agent document and then generate a nested result with selectFields and QueryData like this
ICompanyView {
companyName : 'Warner',
user {
documentId : 'A/1'
firstName : 'john',
lastName : 'paul'
}
}
I need something like the below query that obviously doesn't work as I expect:
const queryData = new QueryData(
["name", "agentDocumentId", "agent.firstName", "agent.lastName"],
["companyName", "user.documentId", "user.lastName", "user.firstName"]);
return await session.query<Company_AllResult>({ index: Company_All })
.whereEquals("companyId", request.companyId)
.include(`agents/${agentDocumentId}`) // ????
.selectFields(queryData,ICompanyView)
.single();
Yes, you can do that using:
https://ravendb.net/docs/article-page/5.4/nodejs/indexes/indexing-related-documents
This is called indexing related documents, and is accessible at indexing time, not query time.
Alternatively, you have the filter clause, which has access to the loaded document, but I wouldn't generally recommend doing this.
Generally:
When you query an index, the results of querying the index are the documents from the collection the index was defined on.
Index-fields defined in the index are used to filter the index-query
but the results are still documents from the original collection.
If you define an index that indexes content from a related-document then when making an index-query you can filter the documents by the indexed-fields from the related documents, but the results are still documents from the original collection.
When making an index-query (or any other query) you can project the query results so that Not the full documents of the original collection are returned but some other object.
Now:
To project/get data from the indexed related-document you have 2 options:
Store the index-fields from the related-document in the index.
(Store all -or- specific fields).
This way you have access to that content when making a projection in your query.
See this code sample.
Don't store the index-fields from the related-document,
then you will be able to use the index-fields to filter by in your query,
but to get content you will need to use 'include' feature in your query,
and then use the session.load, which will Not make another trip to the server.
i.e. https://demo.ravendb.net/demos/nodejs/related-documents/query-related-documents
Good morning colleagues,
I want to make a query regarding how it would be formulated and what would be recommended and the most optimal for making queries with a large number of elements.
I have an api using express that creates a new mongodb model with a unique name and then includes elements inside.
Example:
Collections
*product234 => includes elements => { _:id: ...., name: ... }, { ...}
*product512 => includes elements => { _:id: ...., name: ... }, { ...}
Each collection hosts more than 5000 elements and I want to create a search engine that returns all the results of all the collections that match the "name" that I will send in the request.
How could I perform this query using mongoose? Would it be viable and would it not bring me performance problems by having more than 200 collections and more than 5000 elements in each one?
Answer (Edit):
As i see in the comments the best solution for this for making fast queries is to create a copy of the element with only name or needed values, reference id and reference collection name into a new collection named for example "ForSearchUse" and then make the query to that collection, if complete info is needed then you can query it to the specific collection using the reference id and name of the element
I am creating a collection blog with the following unique index:
{
"title" : 1,
"author" : 1
}
unique:true
This collection consists the following document
{
"title":"Java",
"author":"ABC",
code:123
}
Now I want to insert the following document into it
[{
"title":"JAVA",
"author":"ABC",
code:234
}]
I am using insertMany query to add this to the collection. but the collection has a unique index. so when I try to insert the above document in the collection it will give an error like the title is not unique. but I want check other field error also here so I am using insertMany query with ordered option like:
db.insertMany("blog",[{
"title":"JAVA",
"author":"ABC",
code:234
}]
, {ordered: false})
the above query error gives me all two field names. but when I am trying to use this with Mongodb transaction it will gives only one field error I am using Transaction like:
let session = await db.startSession({});
db.insertMany("blog",[{
"title":"JAVA",
"author":"ABC",
code:234
}]
, {ordered: false, session})
SO how I get all fields name in result whose no unique using insertMany, ordered, and session? Kindly help me here
I noticed that DynamoDB can add and remove items from an array but how do you search for an specific item inside an object if you want to update that one specifically?
For example:
In MongoDB you can search for someitem.$.subitem and update that specific item.
Is there a way on how to do this with DynamoDB?
Item: {
someitem: [
{
subitem: "id",
somevalue: "something"
}
]
}
I would say this is basic functionality but seems not easy to find (or even unsupported)
AWS does not permit to modify it in a single update request more info was found in the following answers:
updating-a-json-array-in-aws-dynamodb.
The solution that they propose is to change the schema from array to {}, or to implement a custom functions and iterate through each array and find your new id to update, so to speak to programatically update your json and then insert whole object.
TableName : 'tablename',
Key : { id: id},
ReturnValues : 'ALL_NEW',
UpdateExpression : 'set someitem['+`index`+'].somevalue = :reply_content',
ExpressionAttributeValues : { ':reply_content' : updateddata }
array element edit via array index
How do you increment multiple fields in one query in mongoose?
For example, here is the working mongo query that I want to use with a mongoose model.
db.users.update({ userId:89 }, { $inc : { "subjectResults.attempts" : 1, "subjectResults.total_time" : 10, "subjectResults.total_score" : 100 } })
The above query is working in plain vanilla Mongo.
Edit: I have removed the confusing property name that lead to the comments below.
The APIs are nearly identical. Instead of db.users.update in straight mongodb, it's UserModel.update in mongoose. Pass in the exact same query and update options object.