including parameters in OPENQUERY...

Question

How can I use a parameter inside sql openquery, such as:

SELECT * FROM OPENQUERY([NameOfLinkedSERVER], 'SELECT * FROM TABLENAME
where field1=@someParameter') T1 INNER JOIN MYSQLSERVER.DATABASE.DBO.TABLENAME
T2 ON T1.PK = T2.PK

Answer 1

You can execute a string with OPENQUERY once you build it up. If you go this route think about security and take care not to concatenate user-entered text into your SQL!

DECLARE @Sql VARCHAR(8000)
SET @Sql = 'SELECT * FROM Tbl WHERE Field1 < ''someVal'' AND Field2 IN '+ @valueList 
SET @Sql = 'SELECT * FROM OPENQUERY(SVRNAME, ''' + REPLACE(@Sql, '''', '''''') + ''')'
EXEC(@Sql)

Answer 2

From the MSDN page:

OPENQUERY does not accept variables for its arguments

Fundamentally, this means you cannot issue a dynamic query. To achieve what your sample is attempting, try this:

SELECT * FROM 
   OPENQUERY([NameOfLinkedSERVER], 'SELECT * FROM TABLENAME') T1 
   INNER JOIN 
   MYSQLSERVER.DATABASE.DBO.TABLENAME T2 ON T1.PK = T2.PK 
where
   T1.field1 = @someParameter

Clearly if your TABLENAME table contains a large amount of data, this will go across the network too and performance might be poor. On the other hand, for a small amount of data, this works well and avoids the dynamic sql construction overheads (sql injection, escaping quotes) that an exec approach might require.

Answer 3

From the OPENQUERY documentation it states that:

OPENQUERY does not accept variables for its arguments.

See this article for a workaround.