ACC2: How to Create Running Totals in a Query
ID: Q132134
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The information in this article applies to:
SUMMARY
Moderate: Requires basic macro, coding, and interoperability skills.
This article demonstrates two methods you can use to create a running
totals query; that is, the total for each record is a summation of that
record and any previous records. This type of query is useful for
displaying cumulative totals over a group of records (or over a period of
time) in a graph or report.
MORE INFORMATIONMethod 1
The first method uses a DSum() function and criteria in a query to create a
running sum over time. The DSum() function sums the current record and any
previous records. When the query moves to the next record, the DSum()
function runs again and updates the cumulative total.
The following sample query uses the Orders table from the sample
database NWIND.MDB to create a running sum of the freight costs for
each month in 1991. The sample data is limited to one year for performance
reasons. Because the DSum() function runs once for every record in the
query, it may take several seconds (depending on the speed of your
computer) for the query to finish processing. To create and run this query,
follow these steps:
- Open the sample database NWIND.MDB.
- Create a new Select query and add the Orders table.
- On the View menu, click Totals.
- In first column of the QBE grid, type the following expression in the
Field box, and make the following selections for the Total, Sort, and
Show boxes:
Field: AYear: DatePart("yyyy",[Order Date])
Total: Group By
Sort: Ascending
Show: Yes
The expression in the Field box displays and sorts the year portion of
the Order Date field.
- In the second column of the QBE grid, type the following expression in
the Field box, and make the following selections for the Total, Sort,
and Show boxes:
Field: AMonth: DatePart("m",[Order Date])
Total: Group By
Sort: Ascending
Show: Yes
The expression in the Field box sorts and displays the month portion
of the Order Date field as an integer value from 1 to 12.
- In the third column of the QBE grid, type the following expression in
the Field box, and make the following selections for the Total and Show
boxes.
NOTE: In the following expression, an underscore (_) at the end of a
line is used as a line-continuation character. Remove the underscore
from the end of the line when re-creating this expression.
Field: RunTot: DSum("Freight","Orders","DatePart('m', _
[Order Date])<=" & [AMonth] & " And DatePart('yyyy', _
[Order Date])<=" & [AYear] & "")
Total: Expression
Show: Yes
The expression in the Field box uses the DSum() function to sum the
Freight field when the values in both the AMonth and the AYear fields
are less than or equal to the current record that the query is
processing.
- In the fourth column of the QBE grid, type the following expression in
the Field box, and make the following selections for the Total, Sort,
and Show boxes:
Field: FDate: Format([Order Date],"mmm")
Total: Group By
Sort: Ascending
Show: Yes
The expression in the Field box displays each month in a textual format,
such a Jan, Feb, Mar, and so on.
- In the fifth column of the QBE grid, type the following expression in
the Field box, and make the following selections for the Total,
Criteria, and Show boxes:
Field: DatePart("yyyy",[Order Date])
Total: Where
Criteria: 1991
Show: No
The expression in the Field box filters the query's recordset to include
only data from 1991.
- Run the query. Note that the RunTot field displays the following records
with a running sum:
AYear AMonth RunTot FDate
--------------------------------
1991 5 514.17 May
1991 6 1225.75 Jun
1991 7 2133.33 Jul
1991 8 3041.5 Aug
1991 9 4052.12 Sep
1991 10 7345.04 Oct
1991 11 8140.26 Nov
1991 12 8933.32 Dec
Method 2
The second method uses a totals query with a DSum() function to create a
running total over a group.
The following sample query uses the Orders table to sum freight costs per
employee as well as to calculate a running sum of the freight. To create
and run the query, follow these steps:
- Open the sample database NWIND.MDB.
- Create a new select query and add the Orders table.
- On the View menu, click Totals.
- In the first column of the QBE grid, add the following field to the
Field box, and make the following selections for the Total and Show
boxes:
Field: EmpAlias: Employee ID
Total: Group By
Show: Yes
This field groups data by Employee ID.
- In the second column of the QBE grid, add the following field to the
Field box, and make the following selections for the Total and Show
boxes:
Field: Freight
Total: Sum
Show: Yes
This field sums the freight data.
- In the third column of the QBE grid, type the following expression in
the Field box, and make the following selections for the Total and Show
boxes.
NOTE: In the following expression, an underscore (_) at the end of a
line is used as a line-continuation character. Remove the underscore
from the end of the line when re-creating this expression.
Field: RunTot: Format(DSum("Freight","Orders","[Employee ID]<=" _
& [EmpAlias] & ""),"$0,000.00")
Total: Expression
Show: Yes
The expression in the Field box uses a DSum() function to sum the
Freight field when the Employee ID is less than or equal to the current
EmpAlias, and then formats the field in dollars.
- Run the query. Note that the RunTot field displays the following records
with a running sum:
EmpAlias SumOfFreight RunTot
------------------------------------
1 $10,450.91 $10,450.91
2 $10,694.25 $21,145.16
3 $13,347.13 $34,492.29
4 $14,046.90 $48,539.19
5 $4,352.02 $52,891.21
6 $4,344.71 $57,235.92
7 $7,967.62 $65,203.54
8 $10,084.86 $75,288.40
9 $3,918.26 $79,206.66
REFERENCES
For more information about a totals query, search for "queries:
calculations," and then "Calculating Totals in a Query" using the Microsoft
Access Help menu.
Keywords : kbusage QryTotal
Version : 2.0
Platform : WINDOWS
Issue type : kbhowto
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