Cosmos DB REPLACE strings in nested Object - azure-cosmosdb

Question

I'm using the Cosmos Data migration tool to migrate data between environments. During my migration, I need to update the hostname of the website in the data. I was able to do this pretty easily with a query like this with the top level object data:
SELECT Farms["name"], Farms["farmerInfo"], REPLACE(Farms["websiteLink"], "thiswebsite", "newHostName") AS websiteLink FROM Farms
My Cosmos DB data is structured like (data is just for the example):
{
"name": "Red's Farm",
"websiteLink": "www.thiswebsite.com/goats/",
"farmerInfo": {
"name": "Bob",
"websiteLink": "www.thiswebsite.com/goats/",
"hasGoats": true,
"numGoats": 17
}
}
I don't actually need to modify any of the top level data. The data I need to modify is within the "farmerInfo" object. I've tried a few things but I've had no luck. How can I replace a string in this object using the SQL api?
I want the data to look like this after the migration:
{
"name": "Red's Farm",
"websiteLink": "www.thiswebsite.com/goats/",
"farmerInfo": {
"name": "Bob",
"websiteLink": "www.newHostName.com/goats/", <--- Updated data
"hasGoats": true,
"numGoats": 17
}
}

Answer 1

You can use a SELECT statement in your SELECT statement to build up the sub objects. As example:
SELECT
c.name,
c.websiteLink,
(
SELECT
c.farmerInfo.name,
REPLACE(c.farmerInfo.websiteLink, "thiswebsite", "newHostName") AS websiteLink
) AS farmerInfo
FROM c