从Azure Comos DB查询并使用Data Factory保存到Azure表存储

Question

I want to save C._ts+C.ttl as one entity in my Azure Table Storage. I do the following query in my Copy Activity:

"typeProperties": {
        "source": {
            "type": "DocumentDbCollectionSource",
            "query": {
                "value": "@concat('SELECT (C.ts+C.ttl) FROM C WHERE (C.ttl+C._ts)<= ', string(pipeline().parameters.bufferdays))",
                "type": "Expression"
            },
            "nestingSeparator": "."
        },

I dont want to copy all the fields from my source ie CosmosDB to my sink ie Table Storage. I just want to store the result of this query as one value . How can I do that?

Answer 1

According to my test, I presume the null value you queried because of that the collection level ttl affects each document , but will not generate ttl property within document.

So when you execute SELECT c.ttl,c._ts FROM c , just get below result.

Document level ttl is not defined, just follow collection level ttl .

You need to bulk add ttl property into per document so that you could transfer _ts+ttl caculator results.

Your Copy Activity settings looks good , just add an alias in SQL, or set the name of the field via column mapping.

Hope it helps you.