As far as I understand the [docs](https://learn.microsoft.com/en-us/sql/relational-databases/performance/joins?view=sql-server-ver15#nested_loops), the Nested Loops operator is a *join* operator, i.e., it requires two *tables* as input.

If that's correct, then why the Nested Loops operator is used with a *Scalar* input?

For example, take the following query (from Paul White's [website](https://www.sql.kiwi/2012/01/dynamic-seeks-and-hidden-implicit-conversions.html)) and its execution plan.
You can see that the inputs for the Nested Loops operator are (1) a Scalar, and (2) a table (the result of the Index Seek).

I know that a scalar can't be joined with a table, then what that actually means? What's actually being joined?

```
USE AdventureWorks2019;
DECLARE @Like nvarchar(50) = N'D%';
SELECT p.[Name]
FROM   Production.Product AS p
WHERE  p.[Name] LIKE @Like;

```

[![enter image description here](https://i.stack.imgur.com/CBvjg.png)](https://i.stack.imgur.com/CBvjg.png)

BTW, I presume that it's a pretty basic question, but I couldn't find a good resource that goes through such basics methodologically, so a recommendation would be much appreciated.