I've been finding as my select criteria get more complex Crystal is having
trouble. For example, if I want to select clients who have not paid and use
a select statement "IsNull(Date_Paid)", and I also have several other select
criteria, Crystal sometimes returns an empty set - but if I make this the
first select statement Crystal seems to do OK. Now if I add a couple of
other complex select statements; for example the client list is large and
sometimes the report is run for individuals but sometimes the report is run
for all clients, I add "ALL" to the parameter default list and create a
select criteria statement "If  ?client = "ALL" then client_name <> "" else
client_name =  ?client". Now I might only want to look at clients still
alive so I add IsNull(Date_of_Death), and I only want to report on clients
of a specific age group so I add parameters for birthdate. My final select
criteria statement might be:

IsNull(Date_Paid) AND
If  ?client = "ALL" then client_name <> "" else client_name =  ?client AND
IsNull(Date_of_Death) AND
Date_of_Birth  IN  {?DateRangeStart} TO {?DateRangeEnd}

I've had Crystal fall on it's face with this type of select criteria. Often
by re-arranging the order of the statements I can get the report to produce
data but I never feel confident it will work all the time.
Has anyone else experienced this problem, and is there a way I can make a
report of this type more reliable?
Thanks in advance for any info,
Bruce

If I tried to put an If ..Then .. Else in the middle of a selection formula I
would expect CR to fall flat on its face.  Deal with these separately.  For
example, you could use the following in Selection Formula:

BooleanVar SelectClient;
If ?client = "ALL" Then
      SelectClient := True
Else
      SelectClient := (client_name =  ?client);

IsNull(Date_Paid) AND
SelectClient AND
IsNull(Date_of_Death) AND
Date_of_Birth  IN  {?DateRangeStart} TO {?DateRangeEnd}

Regards,

John................

If {table.field} < 3 or isnull({table.field} . . . will not work, it wonlt give
you an error message, you just won't get the results you expect.

if isnull(table.field}) or {table.field} < 3. . . will work correctly

(I know this is true with version 7, may not be for later versions)