Get multiple counts with one Cosmos DB query? - azure-cosmosdb

Question

Consider these queries:
SELECT COUNT(1) AS failures 
FROM c 
WHERE c.time = 1623332779 AND c.status = 'FAILURE'
SELECT COUNT(1) AS successes 
FROM c 
WHERE c.time = 1623332779 AND c.status = 'SUCCESS'
How can I combine these two distinct queries into one query?
I tried repurposing the answers from How to get multiple counts with one SQL query?, but ran into a few problems:
COUNT(*) throws an error "Syntax error, incorrect syntax near '*'."
UNION throws "Syntax error, incorrect syntax near 'UNION'."
I also experimented with
SELECT 
SUM(CASE WHEN c.time = 1623332779 THEN 1 else 0 end)
FROM c
but this leads to another syntax error. I noticed that
SELECT COUNT(1) AS mycounter, COUNT(1) AS mycounter2 
FROM c
WHERE c.time = 1623332779
returns
[
{
"mycounter": 3,
"mycounter2": 3
}
]
but I was unable to link these distinct counters to distinct queries.

Answer 1

The following should work. The count operator skips values that are undefined which allows you to filter out rows from it:
SELECT
COUNT(c.status = 'SUCCESS' ? 1 : undefined) AS successes,
COUNT(c.status = 'FAILURE' ? 1 : undefined) AS failures
FROM c
WHERE c.time = 1623332779
It ruins performance though as it doesn't use indexing at all for the count. So you're better off using two seperate queries. If you really want to use a single request you could create a stored procedure that runs both queries and pastes the results together.

Answer 2

Instead of doing counts of the overall query, you can use GROUP BY to get counts in a single query. For example:
SELECT c.time, c.status, COUNT(c.status) AS statuscount
FROM c
WHERE c.time = "1623332779"
GROUP BY c.time, c.status
This won't give you explicit counts called "successes" and "failures" but it will return both counts, something like:
[
{
"time": "1623332779",
"status": "FAILURE",
"statuscount": 123
},
{
"time": "1623332779",
"status": "SUCCESS",
"statuscount": 456
}
]