How to determine the number of records that are returned by a SELECT-SQL statement in Visual FoxPro (113808)

SUMMARY

In Microsoft Visual FoxPro You can create generic SELECT-SQL statements that programmatically produce result sets of records to be output for viewing in a number of ways. However, in certain instances, a SELECT-SQL statement may not produce any records in the query based on the SELECT-SQL criteria provided.

To avoid having a program act upon an empty result, the system variable _TALLY can be evaluated immediately after a query has been executed in order to determine the number of records that have been selected. For more information about _TALLY, see the code example below.

MORE INFORMATION

The following rudimentary example illustrates the usage of the _TALLY system variable. Copy the code into a program (.PRG) file, run the program file, and then follow the prompts that appear on the Visual FoxPro desktop.

   * 
   *
   SET STATUS OFF && SET STATUS BAR OFF in FoxPro for Windows
   fyl = GETFILE('DBF','Choose a table:')
   USE (fyl)
   LIST STRUCTURE
   USE
   ACCEPT 'Enter field list, separated by commas (or ENTER for all):' ;
      TO flds
   IF EMPTY(flds)
      flds='*'
   ENDIF
   ?
   ACCEPT 'Enter conditions (or ENTER for none) ' TO cond
   IF EMPTY(cond)
      cond=''
   ELSE
      cond='WHERE '+cond
   ENDIF

   SELECT &flds FROM (fyl) &cond INTO CURSOR query NOCONSOLE

   IF _TALLY>0
      BROWSE
   ELSE
      WAIT WINDOW 'No matching records found...'
   ENDIF