Microsoft Books Online (BOL) on Using Change Data explains a misleading error messages for cdc.fn_cdc_get_all_changes_* & cdc.fn_cdc_get_net_changes_* when an invalid, out-of-range LSN (Log Sequence Number) has been passed to them.
Msg 313, Level 16, State 3, Line 1
An insufficient number of arguments were supplied for the procedure or function `cdc.fn_cdc_get_all_changes_` ...
Msg 313, Level 16, State 3, Line 1
An insufficient number of arguments were supplied for the procedure or function `cdc.fn_cdc_get_net_changes_` ...
Their explanation on this misleading error message is as following
Note:
It is recognized that the
message for Msg 313 is misleading and
does not convey the actual cause of
the failure. This awkward usage stems
from the inability to raise an
explicit error from within a TVF.
Nevertheless, the value of returning a
recognizable, if inaccurate, error was
deemed preferable to simply returning
an empty result. An empty result set
would not be distinguishable from a
valid query returning no changes.
Here is a demonstration of what the note meant RAISERROR
There are times when I’d like to throw an error and you cannot use TRY..CATCH within UDF since it also has a side-effect like RAISERROR.
Now the question is, how do you get around this problem?
I am sure that you have faced with this restriction before.
What alternative would you suggest?
[UPDATE] Let’s suppose that you are forced to use UDF.
In the case of your function which returns BIT, I’ll return NULL back to the calling code, and at some point after using the function check for NULL, and throw an error then.