I have a form and associated table, that is designed to record hours flown and maintenance requirements. I am using =Dlookup in the Data Control Source field of the property sheet, to copy data from the previous entry.
The fields track maintenance dates, number of days to a maintenance check, hours to a maintenance check, actual hours flown, and the main field total Airframe Hours. These are either Date/Time fields or Number fields. There is an Auto Number field called Uniquekey.
This is a new database and I copied the paper record for the 1st of the month, which was allocated Uniquekey 1, but in DesignView, I get the error indicator box round the [201AirframeHrs] field with "Invalid Control Property: Control Source Circular reference" highlighted.
I realise why, because the command is looking for a figure in its self, so it is a circular equasion. In view, I can't enter any data, so in the table, I put the hours in the box, hoping that with the 2nd and subsequent daily forms it would correct, but it doesn't. The box is empty, and the calculations that rely on it also remain empty.
This is the Expression I am using in the Data Control Source of the AirframeHrs field:
=DLookUp("[201AirframeHrs]","tblACDailyStatus","[Uniquekey] = " & DMax("[Uniquekey]","tblACDailyStatus"))+([201HrsFlown])
I have tried using the 'Ignore' switch, and also adding [Uniquekey>=2], but nothing seems to work. Removing the data control and entering the airframe hours daily, makes all the others fields work, so this seems to be the only problem.
So my question is how and where do I put a number in the first form of a new database, that in following records calculations will be based upon? This must be like an inventory, where the number of widgets are calculated as they come and go, based on a figure somewhere. It is how and where to put that 'somewhere' figure, or is there another way to carry out the calculations?
Any help would be greatly appreciated. Thank you
Norman
The fields track maintenance dates, number of days to a maintenance check, hours to a maintenance check, actual hours flown, and the main field total Airframe Hours. These are either Date/Time fields or Number fields. There is an Auto Number field called Uniquekey.
This is a new database and I copied the paper record for the 1st of the month, which was allocated Uniquekey 1, but in DesignView, I get the error indicator box round the [201AirframeHrs] field with "Invalid Control Property: Control Source Circular reference" highlighted.
I realise why, because the command is looking for a figure in its self, so it is a circular equasion. In view, I can't enter any data, so in the table, I put the hours in the box, hoping that with the 2nd and subsequent daily forms it would correct, but it doesn't. The box is empty, and the calculations that rely on it also remain empty.
This is the Expression I am using in the Data Control Source of the AirframeHrs field:
=DLookUp("[201AirframeHrs]","tblACDailyStatus","[Uniquekey] = " & DMax("[Uniquekey]","tblACDailyStatus"))+([201HrsFlown])
I have tried using the 'Ignore' switch, and also adding [Uniquekey>=2], but nothing seems to work. Removing the data control and entering the airframe hours daily, makes all the others fields work, so this seems to be the only problem.
So my question is how and where do I put a number in the first form of a new database, that in following records calculations will be based upon? This must be like an inventory, where the number of widgets are calculated as they come and go, based on a figure somewhere. It is how and where to put that 'somewhere' figure, or is there another way to carry out the calculations?
Any help would be greatly appreciated. Thank you
Norman
