Parameterized OpenDataSource call

Procedures and functiopns don't like expressions.

Build string first and then pass it to OpenDataSource.

set @FileName = 'c:\foo.xls'
set @dsn='Data Source=' + @FileName+';User ID=Admin;Password=;Extended properties=Excel 8'
SELECT @foo = col1 FROM OpenDataSource( 'Microsoft.Jet.OLEDB.4.0', @dsn)...sheet1

Hello,

When I run the above, I get the following error:

Server: Msg 170, Level 15, State 1, Line 15
Line 15: Incorrect syntax near '@dsn'.

with line 15 being this line:
SELECT @foo = col1 FROM OpenDataSource( 'Microsoft.Jet.OLEDB.4.0', @dsn)...sheet1
                 
I've declared @dsn as:  declare @dsn varchar(400)

Is it something obvious I'm missing?

Thanks.

Actually, OpenDataSource (as well the other functions related) do not accept ANY variables, only fixed string.
Solution is to put all into dynamic SQL:

declare @sql varchar(1000)
set @sql = '
declare @foo ...
SELECT @foo = col1 FROM OpenDataSource( ''Microsoft.Jet.OLEDB.4.0'', ''Data Source="' + @yourfile + '";User ID=Admin;Password=;Extended properties=Excel 8'')...sheet1
'
exec (@sql)

Now, note that @foo is declared inside the dynamic sql, so you won't be able to access it from outside. To solve THAT, you will need to use xp_executesql:
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/tsqlref/ts_sp_ea-ez_2h7w.asp

Cheers

Hello,

Thanks for the information about xp_executesql.  I changed the code to use xp_executesql and it works in the following case:

declare @result varchar(200)

set @SQLString = N'SELECT @foo = col1
FROM      OpenDataSource( ' + '''' + 'Microsoft.Jet.OLEDB.4.0' + '''' + ',' + '''' + 'Data Source="' + 'c:\excel\foo.xls' + '";User ID=Admin;Password=;Extended properties=Excel 8.0'+'''' + ')...sheet1'

SET @ParmDefinition = N'@foo varchar(30) OUTPUT'

EXECUTE sp_executesql
@SQLString,
@ParmDefinition,
@foo=@result OUTPUT
SELECT @result

@result does indeed contain the correct information.  However, getting back to my original question, what I'd *really* like to do is replace the 'c:\excel\foo.xsl' with a variable.  If I add an input variable called 'myfile':

declare @result varchar(200)
declare @FileName varchar(200)
set @FileName = 'c:\foo.xls'

set @SQLString = N'SELECT @foo = col1
FROM      OpenDataSource( ' + '''' + 'Microsoft.Jet.OLEDB.4.0' + '''' + ',' + '''' + 'Data Source="' + @myfile + '";User ID=Admin;Password=;Extended properties=Excel 8.0'+'''' + ')...sheet1'

SET @ParmDefinition = N'@foo varchar(30) OUTPUT,
                                     @myfile varchar(200)'

EXECUTE sp_executesql
@SQLString,
@ParmDefinition,
@myfile=@FileName,
@foo=@result OUTPUT
SELECT @result

it fails:
Server: Msg 137, Level 15, State 2, Line 46
Must declare the variable '@myfile'.

which makes sense because the scope of @myfile is wrong.  So, I guess my new question is: how do I quote the variable @myfile to get SQL Server to expand it at within 'SQLString'?

Thanks for your help!

Success!  

I discovered I had a type-o in my code: the "hard-coded" directory was "c:\excel\foo.xsl" but  my variable @FileName was set to "c:\foo.xsl".  Changing that fixed my problem.  Thanks for your help!