Field to show total from a group of records

[tagteam]

I have a repairs table and I would like to show the total repairs to a car when that car is pulled up in the database. I know it is not suggested to have a calculated field in the table so what is the best way to do this.



I can create a query that will only pull records for that car based on the car id but I am not sure how to get the total to appear in an unbound field. I have created a report that pops up to show the line item repairs and then shows a total but I would like a field that just shows a total and you dont have to click a button to open a query or report.
Thanks

[pbaldy]

A DSum() would be one way, with the appropriate criteria:

DLookup Usage Samples

[tagteam]

Thanks for the input. I have tried

=DSum([Net Charge],[t_Repair],"Criteria = " & [Forms]![f_railcars]![railcarid]=[t_Repair].[railcarID])

Where Net Charge is the field i want to sum, t_repair is the table that Net Charge is in

I am trying to show the total in an unbound field on the form f_railcars and so used the part at the end to try to say. Sum Net Charge from the table t_repair where the current railcarID from the form f_railcars is equal to the railcarID in the table t_repair

However, I am just getting the standard #Name? and no data.

I tried to follow this as the base example DLookup("FieldName", "TableName", "Criteria = " & forms!FormName!ControlName)

[pbaldy]

Criteria would be the name of the field the criteria is to be applied to.

[tagteam]

ok, so i have simplified it to

=DSum([Net Charge],[t_Repair],"[forms]![f_railcars]![railcarid]=[t_Repair].[railcarID]")

sum Net Charge from the table t_repair where the current railcarid = railcar id in the repair table but it still does not work

I also tried putting it in a query and specifying an ID
RepairTotal:dsum("Net Charge","t_repairs", "railcarID=4")

but i get a VBA syntax error and i tried the id from the railcar and the repairs table. I must not be understanding this quite right.

[pbaldy]

The first is wrong; try this for the second:

RepairTotal:dsum("[Net Charge]","t_repairs", "railcarID=4")

railcarID has a numeric data type in the table?

[tagteam]

Thank you for the help, I was able to get it to work by using

=DSum("[Net Charge]","t_Repair","RailcarID = " & [Forms]![f_Railcars]![railcarid])

Apparently Access is a little finicky about where to put the [] and ""

[pbaldy]

Happy to help. The brackets are required because of the inadvisable space in the field name.