OUTPUT variable from dynamic query with openquery

Question

I am working on a dynamic sql statement that uses openquery to retrieve some columns from an Oracle source.  My goal is to take the variables from the select openquery statement and store them, so they can be passed to an insert statement.  I am
having no problem getting the emplid but the first_name and last_name are NULL
Any help would be appreciated.
DECLARE @sql nvarchar(max)
declare @emplid varchar(11)
declare @first_name varchar(50)
set @emplid = '1234'
BEGIN
SET NOCOUNT ON;
SET @sql = 'select distinct emplid,
First_name ,
Last_name
from openquery(DWHCRPT, ''select p.emplid, p.First_nAME, p.last_nAME
FROM PS_OCC_BIODEMO_S P
where P.emplid = ''''' + @emplid + ''''''') A';
EXEC SP_executesql @SQL, N'@emplid VARCHAR (11), @first_name varchar(50) OUTPUT', @emplid, @first_name = first_name;
select @emplid, @first_name --currently returning NULL
END

Answer 1

Patrick's query would work, but it would drag the entire table over to SQL Server, which could be expensive.
The code you posted have several flaws. You are not assigning @first_name, and you have failed to provide OUTPUT for the actual parameter. Also, the DISTINCT looks out of place. Isn't emplid a key?
This should work better:
SET @sql = 'select @first_name = First_name 
        from openquery(DWHCRPT, ''select p.First_nAME, p.last_nAME
                                      FROM PS_OCC_BIODEMO_S P
                   where P.emplid = ''''' + @emplid + ''''''') A'; 
   EXEC SP_executesql @SQL, N'@emplid VARCHAR (11), @first_name varchar(50) OUTPUT', @emplid, @first_name = @first_name OUTPUT;
select @emplid, @first_name --currently returning NULL
Also, look at this link for some tips how to write queries with OPENQUERY without going insane over all nested quotes:
http://www.sommarskog.se/dynamic_sql.html#OPENQUERY
Erland Sommarskog, SQL Server MVP, [email protected]