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Moves the record pointer through the currently selected table and executes a block of commands for each record that meets the specified conditions.

SCAN [NOOPTIMIZE] [Scope] [FOR lExpression1] [WHILE lExpression2]
   [Commands]
   [LOOP]
   [EXIT] 
ENDSCAN

Parameters

NOOPTIMIZE


Prevents Rushmore Query Optimization of SCAN. For more information, see SET OPTIMIZE Command and Using Rushmore Query Optimization to Speed Data Access.
Scope


Specifies a range of records to be scanned. Only the records within the range are scanned. The scope clauses are: ALL, NEXT nRecords, RECORD nRecordNumber, and REST. For more information on scope clauses, see the Scope Clauses online topic. The default scope for SCAN is all records (ALL).
FOR lExpression1


Executes commands only for records for which lExpression1 evaluates to true (.T.). Including the FOR clause lets you filter out records you don't want scanned. Rushmore optimizes a query created with SCANВ ...В FOR if lExpression1 is an optimizable expression. For best performance, use an optimizable expression in the FOR clause. For more information, see SET OPTIMIZE Command and Using Rushmore Query Optimization to Speed Data Access.
WHILE lExpression2


Specifies a condition whereby the commands are executed for as long as lExpression2 evaluates to true (.T.).
Commands


Specifies the Visual FoxPro commands to be executed.
LOOP


Returns control directly back to SCAN. LOOP can be placed anywhere between SCAN and ENDSCAN.
EXIT


Transfers program control from within the SCANВ ...В ENDSCAN loop to the first command following ENDSCAN. EXIT can be placed anywhere between SCAN and ENDSCAN.
ENDSCAN


Indicates the end of the SCAN procedure.

Remarks

SCAN automatically advances the record pointer to the next record that meets the specified conditions and executes the block of commands.

You can place comments after ENDSCAN on the same line. The comments are ignored during program compilation and execution.

SCANВ ...В ENDSCAN ensures that, upon reaching ENDSCAN, Visual FoxPro reselects the table that was current when the SCANВ ...В ENDSCAN loop began.

Example

The following example uses a SCANВ ...В ENDSCAN loop to display all the companies in Sweden.

В Copy Code
CLOSE DATABASES
OPEN DATABASE (HOME(2) + 'Data\testdata')
USE customer  && Opens Customer table
CLEAR

SCAN FOR UPPER(country) = 'SWEDEN'
   ? contact, company, city
ENDSCAN

See Also



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