i have two tables history and jobs
my history table contains
> db.history.find()
{ "id" : "21", "browser" : "FF","os" : "Windows" "datetime" : "2013-11-26 17:04:21", "_id" : ObjectId("5294873d6b441e2c16000002") }
db.jobs.find()
{ "_id" : ObjectId("5289c147db9ed2b022f95a36"), "id" : "21", "launch" : "ertret", "names" : "234", "script" : "art-pagination" }
From the above two tables i need to get browser, launch, script and os by using common id: 21
How it is possible.
You can do it by using following two queries. It is not possible to get it with single query.
> db.history.find({'id':21}, {'browser':1, 'os':1})
> db.jobs.find({'id':21}, {'launch':1,'script':1 })
Related
I have a MongoDB collection "Events" with 1 million documents similar to:
{
"_id" : 32423,
"testid" : 43212,
"description" : "fdskfhsdj kfsdjfhskdjf hksdjfhsd kjfs",
"status" : "error",
"datetime" : ISODate("2018-12-04T15:55:00.000Z"),
"failure" : 0,
}
Considering the documents were sorted based on datetime field (ascending), I want to check them in the chronical order one by one and pick only the records where the "failure" field was 0 in the previous document and it is 1 in the current document. I want to skip other records in between.
For example, if I also have the following records:
{
"_id" : 32424,
....
"datetime" : ISODate("2018-12-04T16:55:00.000Z"),
"failure" : 0,
}
,
{
"_id" : 32425,
....
"datetime" : ISODate("2018-12-04T17:55:00.000Z"),
"failure" : 1,
}
,
{
"_id" : 32426,
....
"datetime" : ISODate("2018-12-04T18:55:00.000Z"),
"failure" : 0,
}
I only want to collect the one with "_id:32425", and repeat the same policy for the following cases.
Of course, if I extract all the data at once, then I can process it using Python for instance. But, extracting all the records would be really time-consuming (1 million documents!).
Is there a way to do the above via MongoDB commands?
I have a database which consists of few collections , i have tried copying from one collection to another .
In this process connection was lost and had to recopy them
now i find around 40000 records duplicates.
Format of my data:
{
"_id" : ObjectId("555abaf625149715842e6788"),
"reviewer_name" : "Sudarshan A",
"emp_name" : "Wilson Erica",
"evaluation_id" : NumberInt(550056),
"teamleader_id" : NumberInt(17199),
"reviewer_id" : NumberInt(1659),
"team_manager" : "Las Vegas",
"teammanager_id" : NumberInt(12245),
"team_leader" : "Thomas Donald",
"emp_id" : NumberInt(7781)
}
here only evaluation id is unique.
Queries that i have tried:
ensureIndex({id:1}, {unique:true, dropDups:true})
dropDups was removed in mongodb ~2.7.
Here is other realization method
but I don't test it
I have two collection as bellow products has reference of user. i search product by name & in return i want combine output of product and user using map reduce method
user collection
{
"_id" : ObjectId("52ac5dd1fb670c2007000000"),
"company" : {
"about" : "This is textile machinery dealer",
"contactAddress" : [{
"address" : "abcd",
"city" : "52ac4bc6fb670c1007000000",
"zipcode" : "39as46as80"
},{
"address" : "abcd",
"city" : "52ac4bc6fb670c1007000000",
"zipcode" : "39as46as80"
}],
"fax" : "58784868",
"mainProducts" : "ads,asd,asd",
"mobileNumber" : "9537236588",
"name" : "krishna steels",
}
"user" : ObjectId("52ac4eb7fb670c0c07000000")
}
product colletion
{
"_id" : ObjectId("52ac5722fb670cf806000002"),
"category" : "52a2a9cc48a508b80e00001d",
"deliveryTime" : "10 days after received the ",
"price" : {
"minPrice" : "2000",
"maxPrice" : "3000",
"perUnit" : "5288ac6f7c104203e0976851",
"currency" : "INR"
},
"productName" : "New Mobile Solar Charger with Carabiner",
"rejectReason" : "",
"status" : 1,
"user" : ObjectId("52ac4eb7fb670c0c07000000")
}
This cannot be done. Mongo support Map Reduce only on one collection. You could try to fetch and merge in a java collection. Couple of days back I solved a similar problem using java collection.
Click to see similar response about joins and multi collection not supported in mongo.
This can be done using two map reduces.
You run your first MR and then you reduce out the second MR onto the results of the first.
You shouldn't do this though. JOINs are not designed to be done through MR, in fact it sounds like you are trying to do this MR with inline output which in itself is a very bad idea.
MRs are not designed to run inline to the application.
You would be better off doing the JOIN else where.
We are playing around with mongodb, but are having som troubles with a query.
We have made a powershell script that fetches drive-info from our servers and saves it in mongodb.
Our model:
{
"_id" : ObjectId("514332334a62a9209c22c866"),
"FreeSpace" : NumberLong("9439911936"),
"Name" : "C",
"TotalSize" : NumberLong("128033222656"),
"Server" : "pcws24",
"Tidspunkt" : ISODate("2013-03-15T14:37:39.457Z")
}
Edit: I have changed the datamodel to this. It should simplify the query.
{
"_id" : ObjectId("514c2ee94a62a914e0bbe954"),
"Server" : "pcws24",
"Tidspunkt" : ISODate("2013-03-22T10:14:01.4Z"),
"Drev" : [{
"DriveLetter" : "C",
"VolumeLabel" : "",
"FreeSpace" : NumberLong("6715068416"),
"TotalSize" : NumberLong("128033222656")
}, {
"DriveLetter" : "D",
"VolumeLabel" : "Data",
"FreeSpace" : NumberLong("80200286208"),
"TotalSize" : NumberLong("159891058688")
}]
}
We have the following use case scenarios.
Get the latest status for each drive on each server.
Get status for the last 24 hours for each drive on each server.
Get status for the last week for each drive on each server.
etc.
The model is created from the Get-Drive cmdlet.
How do we accomplish this? Can it be done with a query or should we use map/reduce?
I have a document and I need to query mongodb database to return me all the documents which was inserted after current document.
Is it possible and how to do that query?
If you do not override the default _id field you can use that objectID (see the mongodb docs) to make a comparison by time. For instance, the following query will find all the documents that are inserted after curDoc has been inserted (assuming none overwrite the _id field):
>db.test.find({ _id : {$gt : curDoc._id}})
Note that these timestamps are not super granular, if you would like a finer grained view of the time that documents are inserted I encourage you to add your own timestamp field to the documents you are inserting and use that field to make such queries.
If you are using Insert time stamp as on of the parameter, you can query like below
> db.foo.find()
{ "_id" : ObjectId("514bf8bbbe11e483111af213"), "Name" : "abc", "Insert_time" : ISODate("2013-03-22T06:22:51.422Z") }
{ "_id" : ObjectId("514bf8c5be11e483111af214"), "Name" : "xyz", "Insert_time" : ISODate("2013-03-22T06:23:01.310Z") }
{ "_id" : ObjectId("514bf8cebe11e483111af215"), "Name" : "pqr", "Insert_time" : ISODate("2013-03-22T06:23:10.006Z") }
{ "_id" : ObjectId("514bf8eabe11e483111af216"), "Name" : "ijk", "Insert_time" : ISODate("2013-03-22T06:23:38.410Z") }
>
Here my Insert_time corresponds to the document inserted time, and following query will give you the documents after a particular Insert_time,
> db.foo.find({Insert_time:{$gt:ISODate("2013-03-22T06:22:51.422Z")}})
{ "_id" : ObjectId("514bf8c5be11e483111af214"), "Name" : "xyz", "Insert_time" : ISODate("2013-03-22T06:23:01.310Z") }
{ "_id" : ObjectId("514bf8cebe11e483111af215"), "Name" : "pqr", "Insert_time" : ISODate("2013-03-22T06:23:10.006Z") }
{ "_id" : ObjectId("514bf8eabe11e483111af216"), "Name" : "ijk", "Insert_time" : ISODate("2013-03-22T06:23:38.410Z") }
>