I am new to CR XI, and am looking at reports another employee wrote years ago.

In one report, there is a parameter where you can choose one or more categories to report on, from a total list of 23 categories.

When I clicked on "Show SQL Query" I was expecting to see something like 23 conditional tests, but the T-SQL I get just shows all 23 selects concatenated with the UNION ALL.

So how does CR know which select to choose?

I looked at the selection expert, and it has 7 lines:

{Command.Category} = {?Category} and
{Command.STATUS} = {?Status} and
(
    {?MyCodes} = "ALL"
    OR
    {Command.THECODE} = {?MyCodes}
)

That's it! Nothing more. No formulas, and no SQL Expression Fields.

Thanks in advance for any advice!