I have the following query in MongoDB which returns a result.
collection.find(eq("name", name)).forEach(printBlock);
How can I collect the results of the above query and pass it to JSP?
I would like if soemone could give an example on how to do this?
Thanks in advance
Related
Is there a way to get an array slice at the mongo db level? I am trying to do something similar to the following: Model.find({filter: option}, startindex, endindex). Currently the only option I found is to do the following:
let result = await Model.find({filter: option});
returh result.slice(startIndex, endIndex)
Unfortunately, this does not work since I have to pull the full record each time. If I can do this at the mongo level that would be great. Thank you for your help!
UPDATE:
After further research I found a possible solution:
Model.find({filter: option}).skip(skip).limit(limit);
it seems with this method I am able to do slice the document array in the mongo db. If you have any other ideas please let me know. Thank you!
from what i know, there isnt a way to get an slice of an array from an document, but there is the select
PS: skip skips the first documents found by the query, and limit limits the amount returned by the query
I try to query documents and get last value from that result by using following query.
dbname.find({"name":"test"}).limit(1).sort({$natural:-1})
But in result I got all the documents which contains name as test.
Kindly let me know where I made mistake
Try please code
dbname.find({}).limit(1).sort({$natural:-1})
You can use below code also
dbname.findOne({name:'test'}).sort({$natural:-1})
I am trying to execute 2 queries at the same time, for example, refer below:
db.getCollection('Test').find({'color':'red'},{'color':'yellow'});
Assume that color red is present in the one collection and yellow is present in another collection, but I am getting the response only from the first query.
Expectation:
1.If both the queries are present in any of the collection I should get both
responses.
2.If anyone of the query is invalid or element is not present in the collection,
I should not get any response.
Thanks in advance
Since you want to match existence of both values, use $all operator:
db.getCollection('Test').find({color:{$all:["red","yellow"]}})
Edit
I managed to get your output, but I think this could be simplified. I thought about different options and ended up in this query:
db.colors.aggregate([{
$facet:{
cond1:[{$match:{color:"red"}}],
cond2:[{$match:{color:"yellow"}}]
}},
{$project:{match1: "$cond1", match2:"$cond2" ,size1:{$size: "$cond1"},
size2:{$size: "$cond2"}}},
{$project:{result:{$cond:[{$and:[{$gte:["$size1",1]},{$gte:
["$size2",1]}]},{$concatArrays:["$match1","$match2"]},[]]}}}
])
I think there is something wrong with your question.
I think you are looking for something like this db.getCollection('Test').find({color: {$in: ['red','yellow']}});
I hope this will help.
Hi I found that the output of the two queries was same, but I want to know is there any difference in executing the query.
First:
db.collectionname.find({}).pretty()
Second:
db.offers.find().pretty()
There is no difference between these two queries.
db.collectionname.find({}).pretty()
You are not giving any query params here so the results are same like
db.collectionname.find().pretty()
In short: Both function in the same way.
1) db.collectionname.find({})
Here you are not specifying any query parameters and its just an empty document {} so it will return you all the documents present in the collection
2) db.offers.find()
Here you didn't specify any queries. So it need not even look at the parameters, it will just print you all the documents in the collection. find() short form of find({})
I am getting query from database.
Using that query I need to run that query and fetch data into collection.
Is there any way??
I have used resultType instead of resulmap and some how I got desired output.