After an upgrade to WF 7703 (from 7611) one of our reports shows the error from the subject. I'm stumped why though...

The code in question is:

DEFINE FILE OEE_DATA
	DATETIME/HMtDYYmA = HINPUT(14,
				EDIT(D4, '$$$99999999')||
				EDIT(D5, '$$$$$999999'), 10, DATETIME);

	INTERVAL/I6 = HDIFF(DATETIME, LAST DATETIME, 'second', INTERVAL);

	TIME_PASSED/I10 = IF LAST DATETIME EQ MISSING
				THEN 5
				ELSE INTERVAL;
END
TABLE FILE OEE_DATA
PRINT DATETIME TIME_PASSED
WHERE RECORDLIMIT EQ 25;
END

Which results in:

 0 ERROR AT OR NEAR LINE      8  IN PROCEDURE ADHOCRQ FOCEXEC *
 (FOC148) ERROR IN USE OF 'IS MISSING'

(I cut the other errors out, they're a result of the above)

What's wrong with this use of IS MISSING?!? At the first record, LAST DATETIME is missing, isn't it?

This message has been edited. Last edited by: Wep5622,

I did find a workaround:

DEFINE FILE OEE_DATA
	DATETIME/HMtDYYmA = HINPUT(14,
				EDIT(D4, '$$$99999999')||
				EDIT(D5, '$$$$$999999'), 10, DATETIME);

	XXX/I1 = 1;
	INTERVAL/I6 = HDIFF(DATETIME, LAST DATETIME, 'second', INTERVAL);

	TIME_PASSED/I10 = IF LAST XXX NE 1
				THEN 5
				ELSE INTERVAL;
END
TABLE FILE OEE_DATA
PRINT DATETIME TIME_PASSED
WHERE RECORDLIMIT EQ 25;
END

I suppose the real question is, what is the value of LAST DATETIME for the first record really? Apparently it's neither MISSING or 0 or '' or HINPUT(1, '0', 10, superfluously_duplicated_variable_name_here)...

Stab in the dark...


should it be 'IS MISSING' in stead of 'EQ MISSING' ?

quote:

Originally posted by Dave:
Stab in the dark...


should it be 'IS MISSING' in stead of 'EQ MISSING' ?

Yes.

-ABT

quote:

should it be 'IS MISSING' in stead of 'EQ MISSING' ?

Interesting, thats in the title.

Wep5622, I do like the solution you used.

Unfortunately EQ MISSING and IS MISSING are equivalent according to the documentation. Reality seems to match the documentation in this case.

That aside, as you can see from the title of this topic, WebFOCUS already interprets my EQ MISSING as IS MISSING, or it wouldn't have known to raise that error

Is the behaviour of LAST defined for the first record of a result set? Is that an uninitialised value, for example? Is there anything we can compare it to in a useful manner, and if so, what is that value for each data type?

In my workaround I used a constant value to match up against LAST, but if the value of LAST XXX is in fact uninitialised, there is theoretically a chance that it is the same value as the chosen constant (1 in this case). Is that correct? If so, how to prevent that?

quote:

DATETIME

This is a define'd field, but it is not defined as being allowed to be missing.
Could that be the issue here?

I thought of that too, but...

The field itself (or the fields it's derived from, rather) isn't actually capable of being MISSING. That's an artifact of the field being used in combination with the LAST function.

The LAST function doesn't have a result field parameter, but if it had it should probably be defined with MISSING.

Wep,

I never use "LAST" in a DEFINE. Because I simple don't know what the "LAST" record... ...in the database.

In a COMPUTE I do know because I just have to look at the BY fields to figure it out.

Could be reason you get a MISSING thinking you're in the first line... ...but it might not be?

i.e. If that DEFINE works ( the source is sorted as needed ) you could use TABLEF to test it.

Greets,
Dave
( it's getting Dutch here. :-)

I think this might be a bug. As far as I know, LAST works with all other data types, including SmartDates, to test the value of a field prior to record #1. Another work-around (besides the one you've already posted), is to test the prior date-time value against the current date-time value instead of against a constant:

TABLE FILE GGSALES
 SUM
  COMPUTE NEW_DATE/YYMD      = DATE ;
  COMPUTE DATE_TIME/HMtDYYmA = HDTTM(NEW_DATE,12,DATE_TIME);
  COMPUTE INTERVAL/I6        = HDIFF(DATE_TIME, LAST DATE_TIME, 'HOURS', INTERVAL);
  COMPUTE TIME_PASSED/I10    = IF (INTERVAL EQ 0) AND (DATE_TIME NE LAST DATE_TIME) THEN 5 ELSE INTERVAL ;
 BY DATE NOPRINT
 WHERE RECORDLIMIT EQ 200 ;
END