I want to count numeric values in my document. I have only simple documents.
{id: ####,
rev: ####,
"name": "Camera SX",
"colour": "white",
"manufacturer": "Sony",
"rec_limit": 180}
I have 420 documents in this structure with difference rec_limit. And I want to sum all rec_limit. How can i do this ? Is there any Map Function?
and how can i get the min rec_limit or max rec_limit ?
Simply create a view that will use such a map function:
function(doc) {
emit(doc.id, doc.rec_limit);
}
In combination with the reduce function: "_stats".
For more informations check out the docs: http://docs.couchdb.org/en/1.6.1/
Related
I am trying to graph data in Azure Timeseries Insights. For the provided sensor, I can only graph the event count - none of the values provided by the JSON are available. Despite this, the raw data is clearly all present.
I can see the attribute state in the raw data, but it cannot be selected for graphing.
The raw data view:
The property selection for the entity:
The raw json (before it lands in Times Series Insights) is as follows (from another identical sensor). The entity_id and last_updated are used as the device id and update time for the event source.:
{
"entity_id": "sensor.temperature_9",
"state": "21.0",
"attributes": {
"on": true,
"unit_of_measurement": "°C",
"friendly_name": "XXXX Schlafzimmer Temp",
"icon": "mdi:thermometer",
"device_class": "temperature"
},
"last_changed": "2021-03-02T07:45:23.239584+00:00",
"last_updated": "2021-03-02T07:45:23.239584+00:00",
"context": {
"id": "32d7edfe14b5738ee47509d026c6d5d3",
"parent_id": null,
"user_id": null
}
}
How can I graph the state from raw data?
Figured it out: the state value from json is used by many objects, some report a numeric value and some an enumeration. This makes the field invalid for direct selection in a numeric data type.
Instead, a value of toDouble($event.state.String) in a type, then assigning the type to the instance, allows the correct value to be displayed.
I'm new to DynamoDB and I'm trying to query a table from javascript using the Dynamoose library. I have a table with a primary partition key of type String called "id" which is basically a long string with a user id. I have a second column in the table called "attributes" which is a DynamoDB map and is used to store arbitrary user attributes (I can't change the schema as this is how a predefined persistence adapter works and I'm stuck working with it for convenience).
This is an example of a record in the table:
Item{2}
attributes Map{2}
10 Number: 2
11 Number: 4
12 Number: 6
13 Number: 8
id String: YVVVNIL5CB5WXITFTV3JFUBO2IP2C33BY
The numeric fields, such as the "12" field, in the Map can be interpreted as "week10", "week11","week12" and "week13" and the numeric values 2,4,6 and 8 are the number of times the application was launched that week.
What I need to do is get all user ids of the records that have more than 4 launches in a specific week (eg week 12) and I also need to get the list of user ids with a sum of 20 launches in a range of four weeks (eg. from week 10 to 13).
With Dynamoose I have to use the following model:
dynamoose.model(
DYNAMO_DB_TABLE_NAME,
{id: String, attributes: Map},
{useDocumentTypes: true, saveUnknown: true}
);
(to match the table structure generated by the persistence adapter I'm using).
I assume I will need to do DynamoDB "scan" to achieve this rather than a "query" and I tried this to get started and get a records where week 12 equals 6 to no avail (I get an empty set as result):
const filter = {
FilterExpression: 'contains(#attributes, :val)',
ExpressionAttributeNames: {
'#attributes': 'attributes',
},
ExpressionAttributeValues: {
':val': {'12': 6},
},
};
model.scan(filter).all().exec(function (err, result, lastKey) {
console.log('query result: '+ JSON.stringify(result));
});
If you don't know Dynamoose but can help with solving this via the AWS SDK tu run a DynamoDB scan directly that might also be helpful for me.
Thanks!!
Try the following.
const filter = {
FilterExpression: '#attributes.#12 = :val',
ExpressionAttributeNames: {
'#attributes': 'attributes',
'#12': '12'
},
ExpressionAttributeValues: {
':val': 6,
},
};
Sounds like what you are really trying to do is filter the items where attributes.12 = 6. Which is what the query above will do.
Contains can't be used for objects or arrays.
Say that this is the table struct:
[{ name:"test", age:99,
Info: [
{ location:"A", num:11 },
{ location:"B", num:99 }
]
}]
What i want to get is something like this:
{ name: "test",
Info:[
{location:"A"},
{location:"B"}
]}
would that be possible? I can't seem to make it work unless I specify the index.
ProjectionExpression="name, #mp[0].location",
Select='SPECIFIC_ATTRIBUTES',
ExpressionAttributeNames={"#mp": "Info"}
How do I do this?
Based on the documentation you can either specify the whole object or with index.
http://docs.aws.amazon.com/amazondynamodb/latest/developerguide/Expressions.Attributes.html#Expressions.Attributes.NestedAttributes
Working as documented.
Hope it helps.
It's a little tricky if you do not know the length of list. You could try using a max length for the list and use something like (assuming 3 is the max length)
ProjectionExpression="#mp[0].location,#mp[1].location,#mp[2].location"
A beginner's question about freebase:
I am looking for the imdb id of a movie called "O". If I use the searchbox on the freebase.com website and constrain the search by type to all:/film/film, then I get a high quality result with the best match on top:
http://www.freebase.com/search?query=o&lang=en&all=%2Ffilm%2Ffilm&scoring=entity&prefixed=true
But this does not include the imdb id. When I try to recreate and refine this search using the query editor, I can't figure out how to do a "general query". The best I could come up with was doing a fuzzy name search like this:
[{
"type": "/film/film",
"name": null,
"name~=": "o",
"imdb_id": [],
"rottentomatoes_id": []
}]
The result contains exactly the information I want, but the movie "O" is only the 12th result in the list, buried under lots of nonsense:
http://www.freebase.com/query?lang=%2Flang%2Fen&q=[{%22type%22%3A%22%2Ffilm%2Ffilm%22%2C%22name%22%3Anull%2C%22name~%3D%22%3A%22o%22%2C%22imdb_id%22%3A[]%2C%22rottentomatoes_id%22%3A[]}]
How can I improve the quality of my result? What special magic does the "?query=o" use that "name~=":"o" does not have?
When you use query=o, freebase does some smart sorting of the results, display exact matches first, followed by less exact matches.
With your query name ~= o you are not searching for movies with name "O", but for movies that contain "O" in their names (the ~= operator). If you want to search for a specific movie title, then specify the exact name:
[{
"type": "/film/film",
"name": "o",
"imdb_id": [],
"rottentomatoes_id": []
}]
This will result in output:
{
"result": [{
"imdb_id": [
"tt0184791"
],
"name": "O",
"type": "/film/film",
"rottentomatoes_id": [
"o"
]
}]
}
If Search gives you the topic that you want, why not just use the output parameter to add the IMDB ID (or whatever else you want) to the output that you request it return?
I have a record
record = [ [ name1:'value1', name2:'value2', name3:'value3' ],
[ name1:'value6', name2:'value7', name3:'value8' ] ]
I would like to add two more key/value pairs to with values as boolean(true/false) as below
record = [ [ name1:'value1', name2:'value2', name3:'value3', name4:false, name5:true ],
[ name1:'value6', name2:'value7', name3:'value8', name4:false, name5:true ] ]
When I tried to use add or put functions, doesnt seem to work(either replacing the existing values or not doing anything)
Just do:
record = record.collect { it + [ name4:false, name5:true ] }
Or you can also do:
record = record*.plus( name4:false, name5:true )
To add to Patricks answer above (+1), a Map contains a set not a list so all keys must be unique. So you cannot assign multiple values to a single key directly.
Among many solutions, you can alternatively, save an object:
Map<String, myObject>
that holds many different values and this will still maintain the uniqueness of the set since there will only be one key.