DSum(expr, domain, [criteria])
The DSum function has the following arguments.
| Argument | Description |
|---|---|
| expr | An expression that identifies the numeric field whose values you want to total. It can be a string expression identifying a field in a table or query, or it can be an expression that performs a calculation on data in that field . In expr, you can include the name of a field in a table, a control on a form, a constant, or a function. If expr includes a function, it can be either built-in or user-defined, but not another domain aggregate or SQL aggregate function. |
| domain | A string expression identifying the set of records that constitutes the domain. It can be a table name or a query name for a query that does not require a parameter. |
| criteria | An optional string expression used to restrict the range of data on which the DSum function is performed. For example, criteria is often equivalent to the WHERE clause in an SQL expression, without the word WHERE. If criteria is omitted, the DSum function evaluates expr against the entire domain. Any field that is included in criteria must also be a field in domain; otherwise, the DSum function returns a Null. |
Remarks
If no record satisfies the criteria argument or if domain contains no records, the DSum function returns a Null.
Whether you use the DSum function in a macro, module, query expression, or calculated control, you must construct the criteria argument carefully to ensure that it will be evaluated correctly.
You can use the DSum function to specify criteria in the Criteria row of a query, in a calculated field in a query expression, or in the Update To row of an update query.
Note You can use either the DSum or Sum function in a calculated field expression in a totals query. If you use the DSum function, values are calculated before data is grouped. If you use the Sum function, the data is grouped before values in the field expression are evaluated.
You may want to use the DSum function when you need to display the sum of a set of values from a field that is not in the record source for your form or report. For example, suppose you have a form that displays information about a particular product. You could use the DSum function to maintain a running total of sales of that product in a calculated control.
TipNote Unsaved changes to records in domain aren't included when you use this function. If you want the DSum function to be based on the changed values, you must first save the changes by clicking Save Record on the Records menu, moving the focus to another record, or by using the Update method.