By using suggestions on Right panel : 

 


Step 1: When you create a new connection, for example as shown here in Connect To hadoop article, you will get to Preview Screen.

 

Step 2: On preview screen, select the column in which you want to get the count pattern. As and when you highlight some values within the column, you can get a suggestion about the count-pattern in the right panel.


Step 3 : When you hover over the suggested option, You will get a preview of the possible output adjacent to the column in light yellow color. 



 

Step 4: You can select the count pattern suggestion from the right panel, and it will apply the selected count-pattern operation on the column and will show the new column adjacent to the selected column with pattern count. The default name of the new created column comes as : "count_pattern_" + columnName You can rename the column as desired.