DocumentDB: How to Update Partial Property Value - azure-cosmosdb

Question

I have been struggling with this for a while. Here is my Document.
{
"id": "1",
"Scenario": "Welcome page",
"Translations": [
{
"Language": "En",
"Content": "Welcome!"
},
{
"Language": "Fr",
"Content": "Bienvenue!"
}
],
"LastModified": "2016-05-27T17:27:58.562-06:00",
"ModifiedBy": "admin",
"LastAccessed": "2016-06-13T10:27:58.562-06:00"
}
And here is my code to update the property (I've hard-coded the value to be modified here):
SqlQuerySpec query = new SqlQuerySpec()
{
QueryText = "SELECT c.id, c.Scenario, t.Language, t.Content, c.LastModified, c.ModifiedBy, c.LastAccessed FROM MultiLanguage as c join t in c.Translations where c.id = #Id and t.Language = #Language",
Parameters = new SqlParameterCollection() { new SqlParameter("#Id", Id), new SqlParameter("#Language", Language) }
};
Document doc = client.CreateDocumentQuery<Document>(
collectionLink, query).AsEnumerable().FirstOrDefault();
doc.SetPropertyValue("Content", "Welcome to Stackoverflow!");
Document updated = await client.ReplaceDocumentAsync(doc);
There are two parameters passed into this function. Id and Language. For example, I only want to update the property Content to "Welcome to Stackoverflow!" for Id = "1" and Language="En". The thing is my code will remove the other "Language": "Fr", "Content": "Bienvenue!" part and update my document to something like this:
{
"id": "1",
"Scenario": "Welcome page",
"Language": "En",
"Content": "Welcome to Stackoverflow!",
"LastModified": "2016-05-27T17:27:58.562-06:00",
"ModifiedBy": "admin",
"LastAccessed": "2016-06-13T10:27:58.562-06:00"
}
But what I want is this:
{
"id": "1",
"Scenario": "Welcome page",
"Translations": [
{
"Language": "En",
"Content": "Welcome to Stackoverflow!"
},
{
"Language": "Fr",
"Content": "Bienvenue!"
}
],
"LastModified": "2016-05-27T17:27:58.562-06:00",
"ModifiedBy": "admin",
"LastAccessed": "2016-06-13T10:27:58.562-06:00"
}
So how can I only update partial property of the document without messing up other properties?

Answer 1

DocumentDB has no update in place. You have to read the doc, update it client side, and then re-save it over the top of the old one. Alternatively, you could denormalize your list of translations into separate documents with "foreign keys" back to the Scenario it relates to.