Working in LINQPad, I am trying to convert a SQL query to a C# functional statement.
The SQL: 

```
SELECT COUNT(DISTINCT([CASE_NO])) FROM [tbl] 

```

I have tried variations of things like: 

```
var cnt = tbl.CASE_NO.Distinct().Count();  
var cnt = tbl.Count(n => n.CASE_NO.Distinct());  

```

"Select the count of distinct CASE\_NO values in the tbl Table".  

I think it is the DISTINCT qualifier that is causing me trouble.

UPDATE: This runs, but with error:  

`var q2 = FL_MODIFies.SelectMany(n => n.CASE_POL_NO.Distinct());`  

`q2.Dump();`  

"Sequence operators not supported for type 'System.String'."