Performance impact on using multiple Where function on Cosmos db query

Question

If I have a querable from a Cosmos DB container. What's the performance impact if I write code in these two different ways?

1. query.Where(x=>x.a=1 && x.b=2);
2. query.Where(x=>x.a=1).Where(x=>x.b=2);

I tried to get the query expression with query.Expression.ToString(), but the output is still very c# code like, not sql-like. So, I don't know what kind of query it will execute on the server side.

Would the two queries generate same/similar server side query?

Is there a way to get the generated sql query like they did in this document?

Thanks

Answer 1

You could try to parse your delegate (Func<>) of IQueryable<> to string to get the desired result.

The LINQ provider for Cosmos DB will combine the conditions into a single WHERE clause on the server side, regardless of whether you used one .Where() or multiple chained calls.

Both your examples will generate the same query:

SELECT * FROM c WHERE c.a = 1 AND c.b = 2

The Cosmos DB LINQ provider is good enough in optimizing the query translation, so you can safely operate the both options.