TURBO BASIC: CREATING MULTIPLE INDICES

  PRODUCT  :  TURBO BASIC                            NUMBER  :  416
  VERSION  :  1.1
   OS  :  PC-DOS
   DATE  :  January 5, 1988                            PAGE  :  1/4

   TITLE  :  CREATING MULTIPLE INDICES




  This  program  shows  you how to create multiple indices with the
  Turbo Basic Database Toolbox.

  The program creates a data file for which each record  contains a
  field  for a person's first name, last  name  and  an  associated
  number. Each of these three  fields has an associated index file.
  The first index  file  is created with high-level TB-Access calls
  and the next two index files are created with low-level TB-Access
  calls. Only the first index file can be  created  with high-level
  TB-Access calls.  All subsequent index files must be created with
  low-level TB-Access calls.

  CLS
  DEFINT A - Z

  CALL  dbInit           'initialize TB-Access constants

  IF Client.File > 0 THEN GOTO EndClientInc 'skip if already open
    INCR LastFileNum
    Client.File = LastFileNum


  'Creates the data file and the index file for first name
  'using high-level TB-Access calls

    CALL dbCreate(Client.File, FileNo, _
      "Example.DBI", 15, "Example.DBD", 40)

    IF dbStatus = %FileAlreadyCreated THEN _
      CALL dbOpen(Client.File, FileNo,      _
        "Example.DBI", 15, 40)

    FIELD FileNo,_
        04 AS Client.Skip$,_
        15 AS First$,_
        15 AS Last$,_
        05 AS S.Num$

  EndClientInc:

  'Creates the index file for last name using
  'low-level TB-Access calls.














  PRODUCT  :  TURBO BASIC                            NUMBER  :  416
  VERSION  :  1.1
   OS  :  PC-DOS
   DATE  :  January 5, 1988                            PAGE  :  1/4

   TITLE  :  CREATING MULTIPLE INDICES




    INCR LastFileNum
    CLIENT.Aux1 = LastFileNum

    CALL MakeIndex(CLIENT.Aux1, "Example.DB1", 15, _
         "Example.DBD", 40, -1)

    IF dbStatus = %FileAlreadyCreated THEN _
      CALL OpenIndex(CLIENT.Aux1, "Example.DB1", 15, _
           "Example.DBD", 40, -1)

  'Creates the index file for the associated number
  'using low-level TB-Access calls.

    INCR LastFileNum
    CLIENT.Aux2 = LastFileNum
    CALL MakeIndex(CLIENT.Aux2, "Example.DB2", 15, _
        "Example.DBD", 40, -1)

    IF dbStatus = %FileAlreadyCreated THEN _
      CALL OpenIndex(CLIENT.Aux2, "Example.DB2",15, _
           "Example.DBD", 40, -1)

  'Sets the file pointer to the beginning of each index file

    CALL ClearKey(Client.Aux2)
    CALL ClearKey(Client.File)
    CALL ClearKey(Client.Aux1)

  INPUT "Enter the number of clients";ClientNum
  FOR I% = 1 TO ClientNum
    INPUT "Enter First Name  :";TFirst$
    INPUT "Enter Last  Name  :";TLast$
    INPUT "Enter Number      :";TS.Num$
    LSET First$ = TFirst$
    LSET Last$  = TLast$
    'RSET is used to insure that the associated numbers are output
    'in numeric ascending order.
    'For example, if the numbers 1, 2, 10 and 11 are entered in any
    'order the effect of the LSET and RSET statements on the
    'associated number field is shown below.

    '  Using LSET                               Using RSET
    '       1                                        1













  PRODUCT  :  TURBO BASIC                            NUMBER  :  416
  VERSION  :  1.1
   OS  :  PC-DOS
   DATE  :  January 5, 1988                            PAGE  :  1/4

   TITLE  :  CREATING MULTIPLE INDICES




    '       10                                       2
    '       11                                      10
    '       2                                       11

    'The ASCII code for a blank is less than the ASCII code for any
    'numeral so CHR$(32) + CHR$(50) <  CHR$(49) + CHR$(48).
    'For more information on the RSET statement refer to page 330
    'of the Turbo Basic reference manual.

    RSET S.Num$ = TS.Num$

    CALL dbWrite(Client.File, First$)
    CALL AddKey(Client.Aux1, DataRef&, Last$)
    CALL AddKey(Client.Aux2, DataRef&, S.Num$)
  NEXT I%

  CLS
  PRINT "FIRST NAME INDEX"
  PRINT "================"
        CALL ClearKey(Client.File)
        CALL dbNext(Client.File, First$)
        WHILE dbStatus = 0
          PRINT First$; "  "; Last$;" ";S.Num$; " "
          CALL dbNext(Client.FIle, First$)
        WEND
  PRINT "LAST NAME INDEX"
  PRINT "==============="
        CALL ClearKey(Client.Aux1)
        CALL NextKey(Client.Aux1, DataRef&, KeyVal$)
        WHILE dbStatus = 0
          CALL GetRec(Client.File, DataRef&)
          PRINT First$; "  "; Last$;" ";S.Num$; " "
          CALL NextKey(Client.Aux1, DataRef&, KeyVal$)
        WEND

  PRINT "NUMBER INDEX"
  PRINT "============"
        CALL ClearKey(Client.Aux2)
        CALL NextKey(Client.Aux2, DataRef&, KeyVal$)
        WHILE dbStatus = 0
          CALL GetRec(Client.File, DataRef&)
          PRINT First$; "  "; Last$;" ";S.Num$; " "
          CALL NextKey(Client.Aux2, DataRef&, KeyVal$)













  PRODUCT  :  TURBO BASIC                            NUMBER  :  416
  VERSION  :  1.1
   OS  :  PC-DOS
   DATE  :  January 5, 1988                            PAGE  :  1/4

   TITLE  :  CREATING MULTIPLE INDICES




        WEND

  CALL dbClose(Client.File)
  CALL CloseIndex(Client.Aux1)
  CALL CloseIndex(Client.Aux2)


  $INCLUDE "DBHIGH.BOX" 'High-level Access calls
  $INCLUDE "DBLOW.BOX"  'Low-level Access calls