Select All option - SSRS

It's often necessary to have a 'select all' option when using parameters in Reporting Services.
Here's a way to do it:

For my report I've created three datasets.

1) The first dataset, named 'Package' creates the parameter values, using UNION command to adjoin a '** SELECT ALL **' value to those obtained from a database.

SELECT '** SELECT ALL **' as PACKAGE

UNION

SELECT PACKAGE.PACKAGE as PACKAGE

FROM PACKAGE

order by PACKAGE.PACKAGE

2) The second dataset, named 'SelectAll' is used to populate the Default Value for the parameter.

SELECT '** SELECT ALL **' as PACKAGE

These two datasets are then used to populate the Report Parameters window as below:

3) The third parameter, in this case named 'ChangedRequest', provides the select logic.

SELECT .....

FROM .....

WHERE PACKAGE.PACKAGE = @Package or '** SELECT ALL **' in (@Package)

order by PACKAGE.PACKAGE

Which results in something like this: