I need to get the record from MongoDB based on the date using MongoDB. I am providing my collection below.
f_task:
{
"_id": "5a13731f9402cc17f81ade10",
"taskname": "task1",
"description": "description",
"timestamp": "2017-11-21 05:58:14",
"created_by": "subhra",
"taskid": "858fca9e2e153a61515c0372e079c521",
"created_date": "21-11-2017"
}
Here I need to fetch record as per created_date. Suppose user input is 20-11-2017 or 22-11-2017 then I need query to get the record if the given date is greater than or less than the "created_date" value.
Related
Im attempting to create this query (which works as I hope)
SELECT userAgent, COUNT(*) FROM page_hour GROUP BY userAgent order by 2 desc limit 10
as a json. I've tried this:
{
"queryType": "groupBy",
"dataSource": "page_hour",
"granularity": "hour",
"dimensions": ["userAgent"],
"aggregations": [
{ "type": "count", "name": "total", "fieldName": "userAgent" }
],
"intervals": [ "2020-02-25T00:00:00.000/2020-03-25T00:00:00.000" ],
"limitSpec": { "type": "default", "limit": 50, "columns": ["userAgent"] },
"orderBy": {
"dimension" : "total",
"direction" : "descending"
}
}
but instead of doing the aggregation over the full range it appears to pick an arbitrary time span (EG 2020-03-19T14:00:00Z)
If you want results from the entire interval to be combined in a single result entry per user agent, set granularity to all in the query.
A few notes on Druid queries:
You can generate a native query by entering a SQL statement in the management console and selecting the explain/plan menu option from the three-dot menu by the run button.
It's worth confirming expectations that the count query-time aggregator will return the number of database rows (not the number of ingested events). This could be the reason the resulting number is smaller than anticipated.
A granularity of all will prevent bucketing results by hour.
A fieldName spec within the count aggregator? I don't know what behavior might be defined for this, so I would remove this property. The docs:
see: https://druid.apache.org/docs/latest/querying/aggregations.html#count-aggregator
Let's assume we have the following collections:
Users
{
"id": MongoId,
"username": "jsloth",
"first_name": "John",
"last_name": "Sloth",
"display_name": "John Sloth"
}
Places
{
"id": MongoId,
"name": "Conference Room",
"description": "Some longer description of this place"
}
Meetings
{
"id": MongoId,
"name": "Very important meeting",
"place": <?>,
"timestamp": "1506493396",
"created_by": <?>
}
Later on, we want to return (e.g. from REST webservice) list of upcoming events like this:
[
{
"id": MongoId(Meetings),
"name": "Very important meeting",
"created_by": {
"id": MongoId(Users),
"display_name": "John Sloth",
},
"place": {
"id": MongoId(Places),
"name": "Conference Room",
}
},
...
]
It's important to return basic information that need to be displayed on the main page in web ui (so no additional calls are needed to render the table). That's why, each entry contains display_name of the user who created it and name of the place. I think that's a pretty common scenario.
Now my question is: how should I store this information in db (question mark values in Metting document)? I see 2 options:
1) Store references to other collections:
place: MongoId(Places)
(+) data is always consistent
(-) additional calls to db have to be made in order to construct the response
2) Denormalize data:
"place": {
"id": MongoId(Places),
"name": "Conference room",
}
(+) no need for additional calls (response can be constructed based on one document)
(-) data must be updated each time related documents are modified
What is the proper way of dealing with such scenario?
If I use option 1), how should I query other documents? Asking about each related document separately seems like an overkill. How about getting last 20 meetings, aggregate the list of related documents and then perform a query like db.users.find({_id: { $in: <id list> }})?
If I go for option 2), how should I keep the data in sync?
Thanks in advance for any advice!
You can keep the DB model you already have and still only do a single query as MongoDB introduced the $lookup aggregation in version 3.2. It is similar to join in RDBMS.
$lookup
Performs a left outer join to an unsharded collection in the same database to filter in documents from the “joined” collection for processing. The $lookup stage does an equality match between a field from the input documents with a field from the documents of the “joined” collection.
So instead of storing a reference to other collections, just store the document ID.
I am trying to figure out specific mongoDb query, so far unsuccessfully.
Documents in my collections looks someting like this (contain more attributes, which are irrelevant for this query):
[{
"_id": ObjectId("596e01b6f4f7cf137cb3d096"),
"code": "A",
"name": "name1",
"sys": {
"cts": ISODate("2017-07-18T12:40:22.772Z"),
}
},
{
"_id": ObjectId("596e01b6f4f7cf137cb3d097"),
"code": "A",
"name": "name2",
"sys": {
"cts": ISODate("2017-07-19T12:40:22.772Z"),
}
},
{
"_id": ObjectId("596e01b6f4f7cf137cb3d098"),
"code": "B",
"name": "name3",
"sys": {
"cts": ISODate("2017-07-16T12:40:22.772Z"),
}
},
{
"_id": ObjectId("596e01b6f4f7cf137cb3d099"),
"code": "B",
"name": "name3",
"sys": {
"cts": ISODate("2017-07-10T12:40:22.772Z"),
}
}]
What I need is to get current versions of documents, filtered by code or name, or both. Current version means that from two(or more) documents with same code, I want pick the one which has latest sys.cts date value.
So, result of this query executed with filter name="name3" would be the 3rd document from previous list. Result of query without any filter would be 2nd and 3rd document.
I have an idea how to construct this query with changed data model but I was hoping someone could lead me right way without doing so.
Thank you
I have created an API in Mule and have a number of queryParameters specified in the RAML file that I would like to use to query my store MongoDB collection.
A snippet of the collection looks like this:
{
"stores": [{
"storeId": 1234,
"storeName": "Shop Around Ltd",
"opens": "09:00:00.000Z",
"closes": "17:00:00.000Z",
"departments": ["clothing", "computers", "toys", "kitchen and home"],
"address": {
"street": "street1",
"city": "New York",
"state": "New York",
"zipCode": "10002"
}
}]
}
My problem is that the query parameters used to query the collection may be different each time so how can I write a dynamic query for MongoDB so it only queries on the fields that have been passed in with values instead of writing a query for each combination of query parameters? E.g. I may want to query based on zip code for one query so all the other fields will be blank and the next time I may want to query on the departments and whether the store will be open at 11am.
The query will be called from Mule.
Thanks
In MongoDB there is a nice tutorial on Manual Reference:
Example:
original_id = ObjectId()
db.places.insert({
"_id": original_id,
"name": "Broadway Center",
"url": "bc.example.net"
})
db.people.insert({
"name": "Erin",
"places_id": original_id,
"url": "bc.example.net/Erin"
})
Note, that this two documents are created at same time.
Question. I need to reference a Customer with an Order, therefore the Customer has been created long time before the Order, how can I add this reference of customer and insert in Order?
Wouldn't you need to do a findOne() on your customer first and add it's id property to your new document?