IF THE ELSE statement in Simple List Report

Hello all. 

I need to have "if then else" statement in simple list report xml view in such case:

IF @Parameter=1

<DatabaseExportDefinition BaseTable="DPRJournalSetup">


</DatabaseExportDefinition> </THEN>

IF @Parameter=2

<DatabaseExportDefinition BaseTable="DialogWatchOperation">



So, i want to use more then one table in my report, depending on @Parameter value. But i can't find true syntax.

Maybe somebody had such problem.

Thanks a lot.