Thanks for your quick response!

The structure of a single stored procedure is alwas the same:

Header (setting variables for the logging table)

Begin try-block

Standard SQL-statements (like Inserting new rows into...

Here's the part of the query which slows the execution down:

...

, T_02_RH_REGIONAL_HIERARCHY T14

, T_14_PL_PLATFORM coguda62

where (T_TD_DATE_HIERARCHIES_DAILY13.TD_KEY = 11

or T_TD_DATE_HIERARCHIES_DAILY13.TD_KEY = 4)

and (1 = 0 or T14.CF_CODE =...

Many thanks for your quick response, that helps much!