Hi all.

I have beat my head on the keyboard for long enough. Here is the query (angle brackets have been replaced by square brackets for readability here)

TEXT TO lcSQL TEXTMERGE NOSHOW PRETEXT 15
    SELECT DATETIME(YEAR(VEH.EvtDate), MONTH(VEH.EvtDate), DAY(VEH.EvtDate), VAL(GETWORDNUM(VEH.EvtTime, 1, ":")), VAL(GETWORDNUM(VEH.EvtTime, 2, ":"))) AS start_time, 
	DATETIME(YEAR(VEH.EvtDate), MONTH(VEH.EvtDate), DAY(VEH.EvtDate), VAL(GETWORDNUM(VEH.EvtTime, 1, ":")), VAL(GETWORDNUM(VEH.EvtTime, 2, ":"))) + ((VAL(GETWORDNUM(VEH.duration, 1, ':')) * 3600) + (VAL(GETWORDNUM(VEH.duration, 2, ':')) * 60)) AS end_time, 
	ST.descr AS SvcType_dsc, SVC.servref 
    FROM funeral!ServiceVehicle VEH WITH (BUFFERING = .T.) 
	JOIN aserdet SVC WITH (BUFFERING = .T.) ON VEH.service_id = SVC.serviceid 
	JOIN psvctype ST ON SVC.servtype = ST.code 
	WHERE VEH.VehCode =  '[[tcVehCode]]'  
		AND VEH.SvcVehID # [[tiSvcVehID]]  
		AND DATETIME(YEAR(VEH.EvtDate), MONTH(VEH.EvtDate), DAY(VEH.EvtDate), VAL(GETWORDNUM(VEH.EvtTime, 1, ":")), VAL(GETWORDNUM(VEH.EvtTime, 2, ":"))) < {[[ttEndTime]]} 
		AND DATETIME(YEAR(VEH.EvtDate), MONTH(VEH.EvtDate), DAY(VEH.EvtDate), VAL(GETWORDNUM(VEH.EvtTime, 1, ":")), VAL(GETWORDNUM(VEH.EvtTime, 2, ":"))) + ((VAL(GETWORDNUM(VEH.duration, 1, ':')) * 3600) + (VAL(GETWORDNUM(VEH.duration, 2, ':')) * 60)) > {[[ttStartTime]]}
ENDTEXT 

It hands me back Function argument value, type, or count is invalid.

Now the goofy thing is that this one works:

TEXT TO lcSQL TEXTMERGE NOSHOW PRETEXT 15
    SELECT DATETIME(YEAR(VEH.EvtDate), MONTH(VEH.EvtDate), DAY(VEH.EvtDate), VAL(GETWORDNUM(VEH.EvtTime, 1, ":")), VAL(GETWORDNUM(VEH.EvtTime, 2, ":"))) AS start_time, 
	DATETIME(YEAR(VEH.EvtDate), MONTH(VEH.EvtDate), DAY(VEH.EvtDate), VAL(GETWORDNUM(VEH.EvtTime, 1, ":")), VAL(GETWORDNUM(VEH.EvtTime, 2, ":"))) + ((VAL(GETWORDNUM(VEH.duration, 1, ':')) * 3600) + (VAL(GETWORDNUM(VEH.duration, 2, ':')) * 60)) AS end_time, 
	ST.descr AS SvcType_dsc, SVC.servref 
    FROM funeral!ServiceVehicle VEH WITH (BUFFERING = .T.) 
	JOIN aserdet SVC WITH (BUFFERING = .T.) ON VEH.service_id = SVC.serviceid 
	JOIN psvctype ST ON SVC.servtype = ST.code 
	WHERE VEH.VehCode =  '[[tcVehCode]]'  
		AND VEH.SvcVehID # [[tiSvcVehID]] 
		AND DATETIME(YEAR(VEH.EvtDate), MONTH(VEH.EvtDate), DAY(VEH.EvtDate), VAL(GETWORDNUM(VEH.EvtTime, 1, ":")), VAL(GETWORDNUM(VEH.EvtTime, 2, ":"))) < {[[ttEndTime]]} 
ENDTEXT 

and this one works:

TEXT TO lcSQL TEXTMERGE NOSHOW PRETEXT 15
    SELECT DATETIME(YEAR(VEH.EvtDate), MONTH(VEH.EvtDate), DAY(VEH.EvtDate), VAL(GETWORDNUM(VEH.EvtTime, 1, ":")), VAL(GETWORDNUM(VEH.EvtTime, 2, ":"))) AS start_time, 
	DATETIME(YEAR(VEH.EvtDate), MONTH(VEH.EvtDate), DAY(VEH.EvtDate), VAL(GETWORDNUM(VEH.EvtTime, 1, ":")), VAL(GETWORDNUM(VEH.EvtTime, 2, ":"))) + ((VAL(GETWORDNUM(VEH.duration, 1, ':')) * 3600) + (VAL(GETWORDNUM(VEH.duration, 2, ':')) * 60)) AS end_time, 
	ST.descr AS SvcType_dsc, SVC.servref 
    FROM funeral!ServiceVehicle VEH WITH (BUFFERING = .T.) 
	JOIN aserdet SVC WITH (BUFFERING = .T.) ON VEH.service_id = SVC.serviceid 
	JOIN psvctype ST ON SVC.servtype = ST.code 
	WHERE VEH.VehCode =  '[[tcVehCode]]'  
		AND VEH.SvcVehID # [[tiSvcVehID]] 
		AND DATETIME(YEAR(VEH.EvtDate), MONTH(VEH.EvtDate), DAY(VEH.EvtDate), VAL(GETWORDNUM(VEH.EvtTime, 1, ":")), VAL(GETWORDNUM(VEH.EvtTime, 2, ":"))) + ((VAL(GETWORDNUM(VEH.duration, 1, ':')) * 3600) + (VAL(GETWORDNUM(VEH.duration, 2, ':')) * 60)) > {[[ttStartTime]]}
ENDTEXT 

So why doesn't it work with both the start time and the end time in the where clause?

TIA