I've been searching for a solution since few hours without success...
I just want to do this request in couchdb with a view:
select * from database where (id >= 3000000 AND id <= 3999999) AND gyro_y >= 1000
I tried this:
function(doc) {
if(doc.id && doc.Gyro_y){
emit([doc.id,doc.Gyro_y], null);
}
}
Here is my document (record in couchdb):
{
"_id": "f97968bee9674259c75b89658b09f93c",
"_rev": "3-4e2cce33e562ae502d6416e0796fcad1",
"id": "30000002",
"DateHeure": "2016-06-16T02:08:00Z",
"Latitude": 1000,
"Longitude": 1000,
"Gyro_x": -242,
"Gyro_y": 183,
"Gyro_z": -156,
"Accel_x": -404,
"Accel_y": -2424,
"Accel_z": -14588
}
I then do an HTTP request like so:
http://localhost:5984/arduino/_design/filter/_view/bygyroy?startkey=["3000000",1000]&endkey=["3999999",9999999]&include_docs=true
I get this as an answer:
{
total_rows: 10,
offset: 8,
rows: [{
id: "f97968bee9674259c75b89658b09f93c",
key: [
"01000002",
183
],
value: null,
doc: {
_id: "f97968bee9674259c75b89658b09f93c",
_rev: "3-4e2cce33e562ae502d6416e0796fcad1",
id: "30000002",
DateHeure: "2016-06-16T02:08:00Z",
Latitude: 1000,
Longitude: 1000,
Gyro_x: -242,
Gyro_y: 183,
Gyro_z: -156,
Accel_x: -404,
Accel_y: -2424,
Accel_z: -14588
}
}
]
}
So it's working for the id but it's not working for the second key gyro_y.
Thanks for your help.
When you specify arrays as your start/end keys, the results are filtered in a "cascade". In other words, it moves from left to right, and only if something was matched by the previous key, will it be matched by the next key.
In this case, you'll only find Gyro_y >= 1000 when that document also matches the first condition of 3000000 <= id <= 3999999.
Your SQL example does not translate exactly to what you are doing in CouchDB. In SQL, it'll find both conditions and then find the intersection amongst your resulting rows. I would read up on view collation to understand these inner-workings of CouchDB.
To solve your problem right now, I would simply switch the order you are emitting your keys. By putting the Gyro_y value first, you should get the results you've described.
Related
I would like to validate results for row count and column freshness on some data on AWS. I am using a check_config.json file to configure the checks. I use terraform to make a Glue job to run the check and throw the result to DynamoDB. The result in DynamoDB is not elaborate and I would like the result to be more specific on the exact results obtained before marking a check as fail or pass. I would like to see, for example, when was the table last modified(column freshness) and number of rows obtained after a count (expect_row_count).
Below is the current result in DynamoDB:
Below is the json code:
{
"table": "table1",
"checks": [
{
"check": "custom_expect_column_to_be_fresh",
"parameters": {
"columns": [
"column1"
],
"strftime_format": "%Y-%m-%d",
"threshold_days": 0,
"threshold_hours": 10
}
},
{
"check": "expect_table_row_count_to_be_between",
"result_format" : "COMPLETE",
"include_config": "True",
"parameters": {
"min_value": 1,
"max_value": 100000
},
"alarm" : {
"threshold": 100,
"period": 3600
}
}
]
}
I was expecting a more elaborate result on how many rows were obtained before the row_count is marked as a failure and I also want to see the last table modification timestamp before column freshness marks as a failure.
I have the following JSON tree from my realtime database:
{
"old_characters" :
{
"Reptile" : {
"kick" : 20,
"punch" : 15
},
"Scorpion" : {
"kick" : 15,
"punch" : 10
},
"Sub-zero" : {
"kick" : 30,
"punch" : 10
}
},
"new_characters" : {
//...ect
}
}
Is it possible to set rules in my firebase console so that I can index my data based on the character with the highest value of kick?
The constraints are:
- character_name are dynamic.
- Key "kick" is static, but its value is dynamic.
Result should be:
Sub-zero first (kick 30)
Reptile second (kick 20)
Scorpion third (kick 15)
What you want seems to be a fairly simple Firebase query on the kick property:
var ref = firebase.dababase().ref('old_characters');
var query = ref.orderByChild('kick');
query.once(function(snapshot) {
snapshot.forEach(function(characterSnapshot) {
console.log(characterSnapshot.key);
console.log(characterSnapshot.child('kick').val());
});
});
You'll note that this prints the results in ascending order. You can:
either reverse the results client-side
or add an inverted property with -1 * score to each character and then order on that
To learn more about the inverting/sorting descending, have a look at some of these previous questions:
firebase -> date order reverse
Sorting in descending order in Firebase database
sorting numbers with firebase
I want to update or create DynamoDB item to get next element:
{
"id": 156,
"date": 12323233.000,
"countries": {
"ua": 1,
"ru": 2}
}
I use python and boto3. So I can check if field countries exist and if not add it. But that will mean 2 DB requests.
table.update_item(
Key={
'id': 156,
'date': date,
},
UpdateExpression='SET countries = if_not_exists(countries, :countries)',
ExpressionAttributeValues={
':countries': {},
},
)
table.update_item(
Key={
'id': 156,
'date': date,
},
UpdateExpression='ADD countries.#country :inc',
ExpressionAttributeNames={"#country": country},
ExpressionAttributeValues={
':inc': 1
},
)
Is there any way to merge this 2 requests in one?
I had to do something like this recently, and took a while to figure out. I've got a count I want to increment if a page doesn't already exist in my set of "done" pages. If not, it increments and adds the page number to the set. Took a while to realize you can 'append' to a list, but have to 'add' to a set.
try:
res = dbt.update_item(
Key={'pk': 'doc3', 'sk': 'na'},
ReturnConsumedCapacity='INDEXES', ReturnValues='ALL_NEW',
ExpressionAttributeNames={
'#count': 'count',
'#done': 'done',
},
ExpressionAttributeValues={
':1': 1,
':page': page,
':pagelist': set([page]),
},
ConditionExpression="(NOT contains(done, :page))",
UpdateExpression="ADD #done :pagelist, #count :1",
)
print(f'rand int page={page} count={res["Attributes"]["count"]}'
f' CU={res["ConsumedCapacity"]["Table"]}')
except ClientError as err:
if err.response['Error']['Code'] == 'ConditionalCheckFailedException':
print('Already got page=%s (%s)' % (page, err))
else:
raise
I want to write a query in Elastic that applies a filter based on values i have in an array (in my R program). Essentially the query:
Matches a time range (time field in Elastic)
Matches "trackId" field in Elastic to any value in array oth_usr
Return 2 fields - "trackId", "propertyId"
I have the following primitive version of the query but do not know how to use the oth_usr array in a query (part 2 above).
query <- sprintf('{"query":{"range":{"time":{"gte":"%s","lte":"%s"}}}}',start_date,end_date)
view_list <- elastic::Search(index = "organised_recent",type = "PROPERTY_VIEW",size = 10000000,
body=query, fields = c("trackId", "propertyId"))$hits$hits
You need to add a terms query and embed it as well as the range one into a bool/must query. Try updating your query like this:
terms <- paste(sprintf("\"%s\"", oth_usr), collapse=", ")
query <- sprintf('{"query":{"bool":{"must":[{"terms": {"trackId": [%s]}},{"range": {"time": {"gte": "%s","lte": "%s"}}}]}}}',terms,start_date,end_date)
I'm not fluent in R syntax, but this is raw JSON query that works.
It checks whether your time field matches given range (start_time and end_time) and whether one of your terms exact matches trackId.
It returns only trackId, propertyId fields, as per your request:
POST /indice/_search
{
"_source": {
"include": [
"trackId",
"propertyId"
]
},
"query": {
"bool": {
"must": [
{
"range": {
"time": {
"gte": "start_time",
"lte": "end_time"
}
}
},
{
"terms": {
"trackId": [
"terms"
]
}
}
]
}
}
}
I have a simple delete operation which goes like this:
{
"TableName":"demo_events",
"Key":{
"category":{"S":"Demo"},
"DynamoID":{"S":"164933868Slt1396454204"}
},
"Expected":{
"category":{
"Exists":true,
"Value"{"S":"Demo"}
}
},
"ReturnConsumedCapacity":"TOTAL",
"ReturnItemCollectionMetrics":"SIZE"}
There is only a single item in database with that ID. The response is this:
{
ConsumedCapacity: {
CapacityUnits: 2,
TableName: 'demo_events'
},
ItemCollectionMetrics: {
ItemCollectionKey: {
category: { S: 'Demo' }
},
SizeEstimateRangeGB: [ 0, 1 ] }
}
Shouldn't this only consume 1 write unit?
Many thanks.
For PutItem, UpdateItem, and DeleteItem, which write only one item, DynamoDB rounds the item size up to the next 1 KB. If you have other attributes in the item in addition to the key attributes, they all together could add up to more than 1 KB.
If there is a Local Secondary Index (LSI) on the table, DeleteItem would also delete the corresponding item from the LSI and item size would contribute to the total Write Capacity Units consumed. DeleteItem response returns an ItemCollectionMetrics when there is a LSI defined for the table. There seems to be a LSI defined for the table based on the sample response
regards