ANOMALIES UPLOADED ON MAY 8, 1989


                                   ANOMALY8.TXT


The following listing addresses seven known anomalies when using
dBASE IV.  Use of these techniques will aid you in avoiding
anomalies that have been reported to our Software Support
Center.  This report will be supplemented as new information is
received.  There is also one Usage Tip that may be used in order
to avoid further problems or misunderstandings when using the
dBASE IV product.



*************************************************************************************


                                   ANOMALIES


SET FIELDS/example contains errors

     The example in "Set Commands", page 3-49 of Language
     Reference for the SET FIELDS TO command contains several
     errors.  In the first example, the fourth line is supposed
     to be a TALK response.  Therefore, the fourth and fifth
     lines should be as follows:
     
        Stock: Record 10
     . LIST NEXT 5
     
     In the second example there are two errors.  The USE command
     should come first, and the SET FIELDS command contains
     unnecessary periods.  The first and second lines should be
     as follows:
     
     . USE Client
     . SET FIELDS TO ALL LIKE *name*
     
================================================================================


FORM/Calculated fields based on other calculated fields 

     Defining a calculated field during CREATE/MODIFY SCREEN 
     based upon another calculated field (that was defined in the
     current screen), will result in a "Variable not found" error
     message.  This limitation does not exist in
     CREATE/MODIFY REPORT.                    
                                           
     EXAMPLE:
     
     Create a screen and define a calculated field that uses an
     existing numeric field in its expression and call it C1. 
     Then attempt to define another calculated field using the
     expression, C1 * 1.  The operation aborts with the
     aforementioned error.
      
     WORKAROUND:
     
     Prior to creation of a screen, define a calculated field for
     C1.
     
     USE Sales                        
     SET FIELDS TO Item,c1=Item * 2    && Item is a numeric field
     
     CREATE SCREEN Sales
     
     Defining another calculated field based upon C1 will not
     return the "Variable not found" error message.
     
================================================================================


LOG()/usage incorrectly explained

     The explanation of the LOG() function is incorrect in
     "Functions" page 4-72 of Language Reference.  In the section
     titled "Usage" it should state that: 
     
     where y is the numeric expression used by the LOG()
     function.
     . . . LOG() returns the value of x, . . . "
     
     When y=e^x, then LOG(y)=x.  
     
     For a referral, the description of LOG() was correct in the
     dBASE III Plus manual, page U 6-50.
     
================================================================================



SET FILTER TO FILE/allows only III+ .QRYs

     To maintain compatibility with dBASE III Plus, dBASE IV
     allows the SET FILTER TO FILE <filename> syntax.  The
     documentation in "Set commands" page 3-50 of Language
     Reference explains that this command, "reads the filter
     condition from a file created by CREATE/MODIFY QUERY."  This
     is misleading, since the queries can only be those created
     in dBASE III Plus (.QRY files).  Queries created in dBASE IV
     (with the extension .QBE), cannot be set via SET FILTER TO
     FILE.  
     
     dBASE IV .QBE files can be activated via SET VIEW TO <.QBE
     or .VUE query filename>.
     
================================================================================
     


Report Forms named "Detail" will not run

     If a report is named "DETAIL", the Detail.FRO file will
     crash with an "Incorrect number of parameters" message when
     the report is run.  No error is returned until the report is
     run.
     
     WORKAROUND:
     
     1) Name report anything but "DETAIL".
     
     2) A fix for this error is now available in the REPORT.GEN
     file dated after 12-9-88, available from The Ashton-Tate
     Bulletin Board, and CompuServe.
     
================================================================================


CONVERT an encrypted file corrupts any locked records

     When a file is encrypted and CONVERTed (or CONVERTed and
     encrypted), and an RLOCK() is executed, any record that is
     locked becomes corrupted.  It is important that you identify
     the chronology of actions made to the file so as to
     successfully retrieve the original unencrypted, unconverted
     file.  
     
     WORKAROUND:
     
     If the file in question was converted and then encrypted,
     the original .DBF file can be retrieved by copying the .CVT
     file to .DBF.  
     
     If the file was encrypted and then converted, the record
     information is lost.  
     (unless the user has made a backup of the original .DBF
     file).
      
================================================================================

                            USAGE-TIP
                                 


APPEND FROM with large number of index tags

     The speed of the APPEND FROM command is markedly affected by
     the number of 
     index tags designated in the production .MDX of the active
     database file.  As the number of active index tags increase,
     the APPEND process will take much longer.  Since a
     production .MDX file is always opened when a file is USEd,
     all tags will have to be updated during an APPEND.  
     
     For the best performance, limit the total number of index
     tags to only those fields or expressions that are most
     commonly required for daily operations.  An .NDX or
     non-production .MDX can be created or maintained for rarely
     used index key expressions.  If using an .NDX file, close
     the .NDX before APPENDing, then open the index and REINDEX. 
     If an .MDX file is desired, use a non-production .MDX and
     close it during the APPEND operation.