I am exploring business calendar functions in teradata. There are some of the business calendar functions like td_week_begin, td_week_end, which takes timestamp with time zone value in first argument and time literal value in third argument, Second argument is the calendar type like iso, teradata.
SELECT TD_WEEK_BEGIN(TIMESTAMP'2014-10-13 15:25:02+10:00','ISO',TIME'09:12:05');
I wanted to know the compution logic of this td_week_begin function when first argument is timestamp and last third argument is time literal. When I do not pass the third optional argument, time literal, I know how this function works, but when for the same value of first argument, If I pass time literal value, the result get change. Somehow this time literal value impacts the value of first argument.
I wanted to know, how this time literal affects timestamp with time zone value.
Please help me in understanding this specific scenario,