Employ SQL-SELECTs "TO SCREEN" clause to determine if a record exists

To determine if a record exists in a table, I used to send the results of a SQL-SELECT to an array, like so:

  LOCAL ARRAY la[FieldName][1]
  _Tally = 0
  SELECT [FieldName]     ;
    FROM [Database]![TableName]    ;
    WHERE [FieldName] = [Memory Variable]  ;
    INTO ARRAY la[FieldName]
  IF _Tally = 0
    MESSAGEBOX(TRANSFORM([Memory Variable]) + ' is not a valid [Whatever] ',
              0, '[MESSAGEBOX() Caption]')
  ENDIF

Sending the results of the SQL-SELECT TO SCREEN NOCONSOLE  obviates the need to declare an array prior to doing the SQL-SELECT:

  _Tally = 0
  SELECT [FieldName]     ;
    FROM [Database]![TableName]    ;
    WHERE [FieldName] = [Memory Variable]  ;
    TO SCREEN NOCONSOLE
  IF _Tally = 0
    MESSAGEBOX(TRANSFORM([Memory Variable]) + ' is not a valid [Whatever] ',
              0, '[MESSAGEBOX() Caption]')
  ENDIF

In different versions of VFP up to and including VFP 8, _Tally was not always reliably accurate (cf. http://foxproadvisor.com/doc/12139 [Cathy Pountney's "_TALLY trap tip]); if that is your experience, simply send the output to a CURSOR and then check the RECCOUNT() of the cursor.

Enjoy!

Art Bergquist