Q62832: 7.00 CREATEINDEX Example Gives "No Current Record" at Run-Time

Article: Q62832
Product(s): See article
Version(s): 7.00 7.10
Operating System(s): MS-DOS
Keyword(s): ENDUSER | docerr SR# S900606-48 | mspl13_basic
Last Modified: 8-JAN-1991

Running the sample program on Page 73 of the "Microsoft BASIC 7.0:
Language Reference" manual returns a run-time error of 85, "no current
record," on the RETRIEVE statement.

The code should be changed as shown below for the program to run
correctly.

This information applies to Microsoft BASIC Professional Development
System (PDS) versions 7.00 and 7.10 for MS-DOS.

The sample program found on Page 73 uses a file called BOOKS.MDB, the
sample ISAM file that SETUP copies to your disk. However, in this
program, the user-defined type, BookRec, does not match the record
structure used in BOOKS.MDB. Also the program specifies a table name
that does not exist in BOOKS.MDB.

The user-defined type, BookRec, should be defined as follows:

   TYPE BookRec
      IDNum AS DOUBLE
      Price AS CURRENCY
      Edition AS INTEGER
      Title AS STRING * 50
      Publisher AS STRING * 50
      Author AS STRING * 36

In addition, the table name should be defined as "BookStock" instead
of "BooksStock".

The corrected program is as follows:

DEFINT A-Z
TYPE BookRec                   'altered user-defined type
   IDNum AS DOUBLE
   Price AS CURRENCY
   Edition AS INTEGER
   Title AS STRING * 50
   Publisher AS STRING * 50
   Author AS STRING * 36
END TYPE

DIM Library AS BookRec
DIM msgtxt AS STRING

CONST Database = "BOOKS.MDB"
CONST TableName = "BookStock" 'TableName = BookStock (not BooksStock)
TableNum = FREEFILE

OPEN Database FOR ISAM BookRec TableName AS TableNum
CREATEINDEX TableNum, "A", 0, "Author"
CREATEINDEX TableNum, "I", 1, "IDNum"
CREATEINDEX TableNum, "T", 0, "Title"
CREATEINDEX TableNum, "C", 0, "Price"
SETINDEX #1, "A"
CLS : LOCATE 13, 30
PRINT "choose a key:"
PRINT SPC(9); "move to:"; TAB(49); " order by: X "
PRINT : PRINT SPC(9); "F - first record"; TAB(49); "A - Author"
PRINT : PRINT SPC(9); "L - last record"; TAB(49); "I - ID number"
PRINT : PRINT SPC(9); "N - next record"; TAB(49); "T - Title"
PRINT : PRINT SPC(9); "P - previous record"; TAB(49); "C - Cost"
PRINT : PRINT SPC(9); "Q - Quit"; TAB(49); "X- no order"
LOCATE 3, 1: PRINT TAB(37); Books; ""
PRINT STRING$(80, "-");
VIEW PRINT 5 TO 10

MOVEFIRST TableNum
DO
    CLS
    RETRIEVE TableNum, Library
    PRINT "Author:   "; Library.Author;
    PRINT TAB(49); "ID #"; Library.IDNum
    PRINT "Title:      "; Library.Title
    PRINT "Publisher: "; Library.Publisher
    PRINT "cost:     "; Library.Price
    PRINT SPC(30); msgtxt
    PRINT STRING$(64, "-")
    IF GETINDEX$(TableNum) = "" THEN
         PRINT STRING$(15, "-");
    ELSE
         PRINT "index in use: "; GETINDEX$(TableNum);
    END IF

     validkeys$ = "FLNPQATICX"
     DO
         keychoice$ = UCASE$(INKEY$)
     LOOP WHILE INSTR(validkeys$, keychoice$) = 0 OR keychoice$ = ""
     msgtxt = ""

     SELECT CASE keychoice$
     CASE "F"
         MOVEFIRST TableNum
     CASE "L"
         MOVELAST TableNum
     CASE "N"
         MOVENEXT TableNum
         IF EOF(TableNum) THEN
             MOVELAST TableNum
             BEEP: msgtxt = "** at last record **"
         END IF
     CASE "P"
         MOVEPREVIOUS TableNum
         IF BOF(TableNum) THEN
             MOVEFIRST TableNum
             BEEP: msgtxt = "** at first record **"
         END IF
    CASE "Q"
         EXIT DO
    CASE ELSE
         VIEW PRINT
         LOCATE 13, 59: PRINT keychoice$;
         VIEW PRINT 5 TO 10
         IF keychoice$ = "X" THEN keychoice$ = ""
         SETINDEX TableNum, keychoice$
         MOVEFIRST TableNum
     END SELECT
LOOP

VIEW PRINT
DELETEINDEX TableNum, "A"
DELETEINDEX TableNum, "I"
DELETEINDEX TableNum, "T"
DELETEINDEX TableNum, "C"
CLOSE
END

THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY.

Copyright Microsoft Corporation 1986-2002.