I have 2 questions:
Does azure Stream analytics support nested conditions using the CASE statement ?
I see there are 2 formats of CASE expression mentioned here- https://learn.microsoft.com/en-us/stream-analytics-query/case-azure-stream-analytics . I found examples for searched CASE here. Can anyone give example for the Simple CASE expression?
Sample data :
[{
"id": "0001",
"type": "donut",
"name": "Cake"
},
{
"id": "0002",
"type": "donut2",
"name": "Cake2"
]
Does azure Stream analytics support nested conditions using the CASE
statement ?
Based on my test, it supports nested case conditions.
SQL:
select jsoninput.id as id, jsoninput.type as type ,
case when
((case when jsoninput.id = '0001' then '0' else '1' end) = '0' ) then '0'
else '1' end as res
from jsoninput
Output:
Can anyone give example for the Simple CASE expression?
SQL:
select jsoninput.id as id, jsoninput.type as type ,
case jsoninput.id when '0001' then 'true' else 'false' end as res
from jsoninput
Output:
Related
I'm trying to understand why my query below will only work when using a subquery.
Sample document structure:
{
"id": "78832-fsdfdf-3242",
"type": "Specific",
"title": "JavaScript vs TypeScript",
"summary": "Explain the differences between JavaScript and TypeScript.",
"products": [
"javascript v6",
"typescript v1",
"node.js"
]
}
Query requirements:
Find the id of all documents where the terms 'javascript' or 'csharp' or 'coding' are contained in either the title, summary or in one of the listed products.
To solve this, I'm using CONTAINS(). To avoid repeating the CONTAINS() for each combination of field and search term, I create a concatenation of the fields in question and name it searchField.
Working query
This is the query I came up with. It's using a subquery sub to add the concatenated fields and products to the result set. Then, I can use CONTAINS() on sub.searchField.
SELECT sub.id
FROM
(
SELECT
o.id,
o.type,
CONCAT(o.title, " ", o.summary, " ", p) as searchField
FROM o
JOIN p in o.products
) sub
WHERE
sub.type = "Specific"
AND
(
CONTAINS(sub.searchField, "javascript", true)
OR CONTAINS(sub.searchField, "csharp", true)
OR CONTAINS(sub.searchField, "coding", true)
)
Non-working query
Originally, I had the query written as seen below. I expected it to work as in other SQL dialects, but I cannot access searchField in the WHERE clause.
"Error: Identifier 'searchField' could not be resolved."
SELECT o.id, CONCAT(o.title, " ", o.summary, " ", p) as searchField
FROM o
WHERE
o.type = "Specific"
AND
(
CONTAINS(searchField, "javascript", true)
OR CONTAINS(searchField, "csharp", true)
OR CONTAINS(searchField, "coding", true)
)
Questions
Is there a better way to achieve the result needed? (Although, surprisingly, the query consumes only 230 RUs)
Why is the subquery needed? I really want to understand this so I can learn when the use subqueries and potentially write queries that would otherwise not be possible.
I have data that looks like: {"id": "abc", "1":"2", "3":"5"}
I'm trying to select this data with this SQL query:
SELECT c.3 FROM c WHERE c.id = '102'
This gives me a syntax error. I also tried c.'3' and "c.3" the and c."3", but none of those worked.
Is there a way to do this?
Please try something like:
SELECT c["1"], c["3"] FROM c WHERE c.id = '102'
It will produce an output like:
[
{
"1": "2",
"3": "5"
}
]
I am trying to extract a specific value from an array property in the Stream Analytics query language.
My data looks as follows:
"context": {
"custom": {
"dimensions": [{
"MacAddress": "ma"
},
{
"IpAddress": "ipaddr"
}]
}
}
I am trying to obtain a result that has "MacAddress", "IpAddress" as column titles and "ma", "ipaddr" as rows.
I am currently achieving this with this query:
SELECT
GetRecordPropertyValue(GetArrayElement(MySource.context.custom.dimensions, 0), 'MacAddress') AS MacAddress,
GetRecordPropertyValue(GetArrayElement(MySource.context.custom.dimensions, 1), 'IpAddress') AS IpAddress,
I am trying to use CROSS APPLY but so far no luck. Below the CROSS APPLY query:
SELECT
flat.ArrayValue.MacAddress as MacAddress,
flat.ArrayValue.IpAddress as IpAddress
FROM
[ffapi-track-events] as MySource
CROSS APPLY GetArrayElements(MySource.context.custom.dimensions) as flat
This one produces two rows instead of one:
MacAddress, IpAddress
ma ,
, ipaddr
so I'm missing precisely the flattening when writing it like that.
I would like to bypass hardcoding the index 0 as it's not guaranteed that MacAddress won't switch places with "IpAddress"... So I need something like FindElementInArray by condition, or some means to join with the dimensions array.
Is there such thing?
Thank you.
I would like to understand how to create query where clauses on DocumentDB with mathematical comparator inside.
For example, I used this demonstrator to understand how to make a "greater than" comparaison : expression AND food.version > 0 seems to work very well.
Here is under what I tryed onto portal.azure.com documentdb query explorer and the results. I don't understand why I got an error in some cases(QUERY3), and (in option) how to get error details on portal.azure.com ?!
Tested:
>>> QUERY1 >>
SELECT d.id,
d.name,
d.lastUpdateTime
FROM d
>>> RESULT1 >>
[
{
"id": "558d6007b909e8dfb2286e7b",
"name": "cSimpleSIMS_ici",
"lastUpdateTime": 1435589982672
},
{
"id": "558d6009b909e8df18296e7b",
"name": "didier",
"lastUpdateTime": 1435330811285
},
{
"id": "558d600ab909e8df28296e7b",
"name": "cDoubleSIMD_ici",
"lastUpdateTime": 1435331176750
},
{
"id": "558d600bb909e8df55296e7b",
"name": "george",
"lastUpdateTime": 1435330813519
}
(...)
]
>>> QUERY2 >>
SELECT d.id,
d.name,
d.lastUpdateTime
FROM d
WHERE (d.name='george')
>>> RESULT2 >>
[
{
"id": "558d600bb909e8df55296e7b",
"name": "george",
"lastUpdateTime": 1435330813519
}
]
>>> QUERY3 >>
SELECT d.id,
d.name,
d.lastUpdateTime
FROM d
WHERE (d.lastUpdateTime > 14)
>>> RESULT3 IN ERROR!
>>> QUERY4 >>
SELECT d.id,
d.name,
d.lastUpdateTime
FROM d
WHERE (d.name='george' AND d.lastUpdateTime > 14)
>>> RESULT4 >>
[
{
"id": "558d600bb909e8df55296e7b",
"name": "george",
"lastUpdateTime": 1435330813519
}
]
>>> QUERY5 >>
SELECT d.id,
d.name,
d.lastUpdateTime
FROM d
WHERE (d.name='george' AND d.lastUpdateTime > 1435330813519)
>>> RESULT5 >>
[]
Here's the gist...
Today, all JSON properties in DocumentDB get automatically indexed by a Hash index; which means queries with equality operators (e.g. WHERE d.name= "george") are extremely fast.
On the other hand, range queries (e.g. WHERE d.lastUpdateTime > 14) require a range index to operate efficiently. Without a range index, the range query will require a scan across all documents (which we allow if the header, x-ms-documentdb-query-enable-scan, is passed in by the request).
The queries you issued that had both a equality and range filter (e.g. WHERE d.name='george' AND d.lastUpdateTime > 14) succeeded, because the equality filter greatly narrowed down the set of documents to scan through.
TL;DR: There are two things you can do here to get rid of the error:
Create a custom index policy to add a range index for numeric types. The documentation for indexing policies can be found here.
Issue your query programmatically (not through the Azure Portal) to set the x-ms-documentdb-query-enable-scan header to allow scans on range queries.
P.S. I will push to improve the Azure Portal for you.
Now... there appear to be a few issues in the Azure Portal - which I will push to get fixed for you.
Bug: Exception message is truncated
Looks like the meaningful part of the exception message gets truncated out when using the Azure Portal - which is no bueno. What SHOULD have been displayed is:
Microsoft.Azure.Documents.DocumentClientException: Message: {"Errors":["An invalid query has been specified with filters against path(s) that are not range-indexed. Consider adding allow scan header in the request."]}
Missing Feature: Enabling scans in query explorer
There ability to set the x-ms-documentdb-query-enable-scan header is currently not exposed in the Azure Portal's query explorer. We will add a checkbox or something for this.
To add to aliuy's answer, we're working on a change that will improve the developer experience here - Default indexing policy for numbers will be changed from Hash to Range index, so you do not need the header or override indexing policy in order to perform range queries.
I have stored the following JSON document in the Azure Document DB:
"JobId": "04e63d1d-2af1-42af-a349-810f55817602",
"JobType": 3,
"
"Properties": [
{
"Key": "Value1",
"Value": "testing1"
},
{
"Key": "Value",
"Value": "testing2"
}
]
When i try to query the document back i can easily perform the
Select f.id,f.Properties, C.Key from f Join C IN f.Properties where C.Key = 'Value1'
However when i try to query:
Select f.id,f.Properties, C.Key from f Join C IN f.Properties where C.Value = 'testing1'
I get an error that the query cannot be computed. I assume this is due to 'VALUE' being a reserved keyword within the query language.
I cannot specify a specific order in the property array because different subclasses can add different property in different orders as they need them.
Anybody any suggestion how i can still complete this query ?
To escape keywords in DocumentDB, you can use the [] syntax. For example, the above query would be:
Select f.id,f.Properties, C.Key from f Join C IN f.Properties where C["Value"] = 'testing1'