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SUM Command

  • Cikk

Totals all or specified numeric fields in the currently selected table.

SUM [eExpressionList]   [Scope] [FOR lExpression1] [WHILE lExpression2]
   [TO MemVarNameList | TO ARRAY ArrayName]   [NOOPTIMIZE]

Parameters

  • eExpressionList
    Specifies one or more fields or field expressions to total. If you omit the field expression list, all numeric fields are totaled.

  • Scope
    Specifies a range of records to include in the total. The scope clauses are: ALL, NEXT nRecords, RECORD nRecordNumber, and REST. For more information on scope clauses, see the Scope Clauses or Overview of the Language online topics.

    The default scope for SUM is ALL records.

  • FOR lExpression1
    Specifies that only the records for which the logical condition lExpression1 evaluates to true (.T.) are included in the total. Including FOR makes it possible for you to conditionally total records, filtering out undesired records.

    Rushmore optimizes a SUM ... FOR command if lExpression1 is an optimizable expression. For best performance, use an optimizable expression in the FOR clause.

    For more information on Rushmore optimization, see SET OPTIMIZE and Using Rushmore to Speed Data Access.

  • WHILE lExpression2
    Specifies a condition whereby records from the current table are included in the total for as long as the logical expression lExpression2 evaluates to true (.T.).

  • TO MemVarNameList
    Stores each total to a variable. If you specify a variable in MemVarNameList that doesn't exist, Visual FoxPro automatically creates it. Separate the variable names in the list with commas.

  • TO ARRAY ArrayName
    Stores totals to a variable array. If the array you specify in SUM doesn't exist, Visual FoxPro automatically creates it. If the array exists and is too small to contain all the totals, the size of the array is automatically increased to accommodate the totals.

  • NOOPTIMIZE
    Disables Rushmore optimization of SUM.

    For more information, see SET OPTIMIZE and Using Rushmore to Speed Data Access.

Example

The following example displays the totals of the in_stock and on_order fields in the products table, along with a sum of the two totals.

CLOSE DATABASES
OPEN DATABASE (HOME(2) + 'data\testdata')
USE products  && Opens Products table

SUM in_stock, on_order, in_stock+on_order ;
   TO gnInStock, gnOnOrder, gnUnits

CLEAR
?
? 'Total in stock : ', gnInStock  && Displays 3119.00
? 'Total on order:  ', gnOnOrder  && Displays 780.00
? 'Total # units :  ', gnUnits  && Displays 3899.00

See Also

AVERAGE | CALCULATE | COUNT | SET OPTIMIZE | Using Rushmore to Speed Data Access | Scope Clauses | Overview of the Language