Cognos: Ranking using RowNumber() Function

Sometimes we may find hard to use rank function in our report to display Top-N rows. This can be easily solved using RowNumber function. Here are the steps

- Create a prompt with parameter name 'p_rank'
- Create a boolean variable

RowNumber()<=string2int32 (ParamValue('p_rank'))

- select the column on which you want to rank
- Click on Style Variable under Properties window and select the boolean variable
- Click Condition Explorer and select boolean variable value 'No'
- Select Box Type to None
- Run the report