Hmm... so you just executed the statement
select calmonth from pruning_test where calmonth = '201502';
right?
The thing is, that SAP HANA Studio by default always prepares and then executes the statement.
You can switch this off in the settings and then you should be able to distinguish between prepare and execute.
I recommend to also make use of JDBC tracing of SAP HANA studio, so that you have a better grip on what commands are actually send to SAP HANA.