winfave@dutrun.UUCP (Alexander Verbraeck) (12/21/89)
Up till now, I have developed quite a lot of software using Turbo Pascal
(2.0, 3.0, 4.0, 5.0 and recently 5.5) with the database toolbox
(currently version 4.0). One of my customers used the program and added
some 3000 records to the database. Everything worked fine until the
3170th record was reached. The database still works fine (FindKey,
GetRec, PutRec etc.), but the index seems corrupt. After a ClearKey
followed by a repeat ... NextKey ... until (not OK) or ... the program
either hangs or gives a Disk Read Error.
Of course I tried debugging the program using the Turbo Debugger, and it
seems there is an illegal record number somewhere in the B-tree. I
rebuilt the index a zillion times, but the error persists. I traced the
procedures and it seems to go wrong during a PutRec (???) called from
TAGetPage. The strange thing is that TAGetPage has the following header:
procedure TAGetPage(var IdxF : IndexFile;
R : Integer;
var PgPtr : TaPagePtr);
R is an integer in this header. When calling TAGetPage, a parameter R of
type Longint is passed. The R is used in the PutRec call. Is this a
error? Does someone have a more recent version of the Turbo Database
toolbox with a changed header of the TAGetPage procedure?
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Alexander Verbraeck e-mail: winfave@dutrun.tudelft.nl
Delft University of Technology winfave@hdetud1.bitnet
Department of Information Systems winfave@dutrun.uucp
PO Box 356, 2600 AJ The Netherlands dutrun!winfave@hp4nl.uucp
----------------------------------------------------------------------mike@raven.USS.TEK.COM (Mike Ewan) (12/22/89)
In article <1052@dutrun.UUCP> winfave@dutrun.UUCP (A.Verbraeck) writes: [...] >(currently version 4.0). One of my customers used the program and added >some 3000 records to the database. Everything worked fine until the >3170th record was reached. The database still works fine (FindKey, >GetRec, PutRec etc.), but the index seems corrupt. After a ClearKey >followed by a repeat ... NextKey ... until (not OK) or ... the program >either hangs or gives a Disk Read Error. I ran into the same problem. Here's the solution, first when you 'tabuild' the taccess unit, it assumes the max number of records is 1000. So your page sizes are wrong for anything over that. What you need to do is run 'tabuild /W+ file.typ'. Then when the configuration screen comes up select the max number of records as something like 32000. There's little overhead for large number and it'll sure save a lot of headaches later. You can also play around with the entries per page and page stack size variables if you want.