HDTenEightyP/NetNews huggingface dataset:
From: dtb@otto (David Bath)
Newsgroups: comp.databases
Subject: Re: Hierarchical Structures in RDBMS
Date: 8 Jan 93 04:36:24 GMT
Organization: RMIT Computer Centre
NNTP-Posting-Host: otto.bf.rmit.oz.au

tchild@autodesk.com (Timothy Child) writes:

>In article 5870@devon.co.uk, don@duncan (Don Radvan) writes:
>> 
>> I have an interesting problem. I need to represent hierarchical data  
>> structures within a relational db, but I need to do it in a way that  
>> permits the user to create his own hierarchy. That is, I do not know the  
>> structure of the hierarchy before hand. 
>> 
>> For example:
>> 	A user wants to organize various objects. These objects will  
>> appear as leaf nodes in the user's own hierarchy. The user may choose many  
>> different ways of organizing these objects, indeed, s/he may have many  
>> simultaneous hierarchies of organization for each set of objects. What  
>> results is a sort of directory tree. Each directory is a category of  
>> objects and each "file" or non-directory entry in a directory is an  
>> object. Given the objects of apples and oranges, we may get the following:
>> 
>>                                   Stuff
>>                                     |
>>                     --------------------------------
>>                   Food                          Non-Food
>>                     |
>>             ---------------------- . . .
>>          Fruit        Veggies 
>>            |
>>      -------------
>>   Apples       Oranges
>> 
>> And so when s/he does a query such as the following:
>> 	select name where Food = "Fruit"
>> or
>> 	select name where Stuff = "Food" AND Food = "Fruit"
>> 
>> we would get Apples and Oranges.
>> 

> It's possible to model this problem with an RDBMS, but I don't know of
> a STANDARD way to express the appropriate SQL to return the information
> and I don't think there is one!  

ORACLE has a lovely CONNECT BY PRIOR clause that joins leaves to nodes.

Very sexy if you like trees.  I do not think other RDBMS have this
facility short of doing it by hand (and blowing your cursor limit).


David T. Bath	Email:dtb@otto.bf.rmit.oz.au	Phone:03-3477511
Global Technology Corporation, 179 Grattan St, CARLTON, VIC, 3153, AUSTRALIA
"Failure to emulate is the best revenge" - Marcus Aurelius
-- 
David T. Bath	Email:dtb@otto.bf.rmit.oz.au	Phone:03-3477511
Global Technology Corporation, 179 Grattan St, CARLTON, VIC, 3153, AUSTRALIA
"Failure to emulate is the best revenge" - Marcus Aurelius
Newsgroups: comp.databases
Subject: Re: What is a NULL, is there a proper definition?
From: ballpe@cbr2
Date: 8 Jan 93 09:33:48 GMT

In article <1iffrnINN57c@ceres.kingston.ac.uk>, cs_b153@ceres.kingston.ac.uk (Greg Royle) writes:
> Hi All out there,
> 	I am looking for literature (anything) on NULLS. Is there such
> literature on how different types of Database deal with the concept of NULL.
> Is there a definition of NULL other than "Well! it fills a GAP".
>

The following quote comes from "Using SQL" by James R. Groff and Paul N.
Weinberg, Osborne McGraw-Hill, ISBN 0-07-881524-X :

"SQL supports missing, unknown, or inapplicable data explicitly, through the
concept of a null value. A null value is an _indicator_ that tells SQL (and the
user) that the data is missing or not applicable. As a convenience, a missing
piece of data is often said to have the value NULL. But the NULL value is not a
real data value like 0, 473.83, or "Sam Clark". Instead, it's a signal, or a
reminder, that the data value is missing or unknown."


> 	Please can you send me any information ,no matter if you think it
> irrelevant, so I can browse through and study it. Tell me how you have used
> NULLS in your everyday life etc. Are there any areas where I can obtain the
> information electronically? Any help will be deeply appreciated.
> 
> 
> 		Many regards,
> 
> 			Greg Royle. 

We use NULLs exactly as the quote says, as an indicator that a value is unknown
or missing. I strongly recommend you purchase the book I mentioned (or a
similar text). It was recommended by a trade magazine (DBMS I think) and is a
very good reference book on the SQL standard.

Hope this is of some help.


Peter Ball
Systems Development Officer
Information Services
Dept of Health, Housing and Community Services
Brisbane, QLD, Australia
"These views are my own and my employer wants nothing to do with them!"
From: someday@hardy.u.washington.edu (Scott Johnson)
Newsgroups: comp.databases
Subject: Re: popup that maintains cursor position on redisplay in Revelation
Keywords: Revelation popup
Date: 11 Jan 93 06:49:23 GMT
Article-I.D.: shelley.1ir59jINN5vu
Organization: University of Washington, Seattle
NNTP-Posting-Host: hardy.u.washington.edu

In article <1993Jan11.035408.16861@massey.ac.nz> D.M.Todd@massey.ac.nz (D.M. Todd) writes:
>How can I set up a popup in Advanced Revelation (3.x) that will return
>to the same row after it is executed.  Ordinarily a redisplayed popup
>will place the cursor on row 1, but I'd like it to put the cursor on
>the row that was previously selected.
>
>Any help will be much appreciated.

I'm not clear on what you mean by "return...after it is executed".
But if you mean you are repeatedly displaying a popup by a direct call
to the POP.UP() function, then you can position the highlight bar on a
specific row by setting field <2> of the coordinates (11th) argument.
Example (off the top of my head):
 
  selection = 1
  loop
    coordinates = ""
    coordinates<2> = selection
    selection = pop.up( ........... , coordinates , ... )
  while selection <> NULL$
    gosub process_selection
  repeat

(Assuming the usual EQUATEs and DECLAREs at the top of the code.)
This fragment would repeatedly display a popup as the user makes
selections, until the user quits by pressing [Esc].  Each time around,
it positions the highlight on the previous selection.  Is this it?

-Scott
Newsgroups: comp.databases
From: daniel@borland.com (Dan Veditz)
Subject: Re: dBASE IV and foreign language
Originator: daniel@genghis.borland.com
Organization: Borland International
Date: Tue, 5 Jan 1993 20:17:15 GMT

<HAWES@MAINE.MAINE.EDU> writes:
> About six months ago, I posted a query regarding sorting and/or
> indexing on mixed French/English text.  I was looking for a way
> to correctly sort a mixed French/English bibliographic database
> in which extended ASCII accented characters were used for French
> citations.
>
> One responder, apparently a programmer for Ashton-Tate, said that
> he had been involved in preparing version 1.5 of dBASE IV, and
> that that version would accommodate "foreign language" characters.
> I suggested that I get a copy of dBASE IV 1.5.

In dBASE IV version 1.5 we added a config.db command called LANGTABLES.  
The default for the English version is OFF, so you get an ASCII sort 
and only a-zA-Z are alphabetics.  If you set LANGTABLES = ON in your 
config.db you will get an international sort and the accented characters 
in the extended ASCII range will be considered alphabetics for things 
like ISALPHA() and PICTURE/FUNCTION clauses, UPPER() and LOWER() will 
work correctly with them and so on.

If the "International English" language tables don't quite do it
for you or you want to support a codepage other than 437 you can
call Borland Tech Support (Customer Service?) and ask for the
"Language Support Disk" for dBASE IV version 1.5 which will allow
you to install language tables for 22 different country/codepage
combinations.  As far as I know the Language Support Disk is only
available for the English versions of dBASE, but if you have a translated
version of dBASE and need that capability go ahead and contact us and
we should be able to help you out with no problems.

WARNING: If you change your collation (sort) order you must reindex
all your files!  If you use an existing index with a dBASE that
now "thinks" in a different collation you will corrupt the index file.
If you use the index Read Only you will not technically corrupt it, 
but some records may *appear* to have vanished to certain operations.

  Dan Veditz
  Borland International
  International R&D, dBASE
  daniel@borland.com
Newsgroups: comp.databases
From: durai@ortta.umn.edu (Durai Venkatasubramanian)
Subject: Re: Foxpro and Insufficient Memory Errors
Organization: U of Mn
Date: Fri, 8 Jan 1993 14:49:12 GMT

In article <1993Jan7.222734.20312@nntpd2.cxo.dec.com> scott@talguy.cxo.dec.com (Scott Johnson) writes:
>From: scott@talguy.cxo.dec.com (Scott Johnson)
>Subject: Foxpro and Insufficient Memory Errors
>Date: Thu, 7 Jan 1993 22:27:34 GMT

>Is there a command I can run ocassionally during the execution of the program
>which will cut down and possibly reclaim unused memory?  I was hoping there
>was some sort of garbage collection routine that can be invoked once in a 
>while during the execution cycle of the application.

4mg to me is quite a lot of memory.  You should not get "insufficient 
memory" errors, unless you have tons of TSRs out there, or you are using 
some kind of task switcher to manage multiple applications.  Assuming you 
can get rid of unwanted TSRs,...may be you can try one or more of the 
following.

1. Is DOS loaded high ?
2. Are you using foxpro extended version ? <it will take advantage of upper 
   memory>
3. Are you using any expanded memory managers ? <ms-dos includes himem.sys, 
   and emm386 that help you access the upper memory area.  make sure you use 
   them, unless you want third party memory managers.  again, if you are 
   using emm386, you should have device=emm386.sys in your config.sys, 
   otherwise the 3mg of memory will be ignored>
4. mem command (dos) will display the amound of used and free memory in 
   the system (mem has several switches)
5. in your config.fp, if "dosmem = on", foxpro will use all dos memory with 
   any extended memory
6. check you config.sys for files, buffers entries <buffers hog memory>
7. sys(12)  : remaining memory
   sys(23)  : ems usage
   sys(24)  : ems limit
   sys(1001): foxpro's memory
   sys(1016): memory used by user objects
8. if you are using foundation read (or any other type of event driven 
   interface), you might use up a lot of memory
Organization: University of Maine System
Date: Tuesday, 5 Jan 1993 11:26:12 EST
From: <HAWES@MAINE.MAINE.EDU>
Newsgroups: comp.databases
Subject: dBASE IV and foreign language

About six months ago, I posted a query regarding sorting and/or
indexing on mixed French/English text.  I was looking for a way
to correctly sort a mixed French/English bibliographic database
in which extended ASCII accented characters were used for French
citations.

One responder, apparently a programmer for Ashton-Tate, said that
he had been involved in preparing version 1.5 of dBASE IV, and
that that version would accommodate "foreign language" characters.
I suggested that I get a copy of dBASE IV 1.5.

Universities work slowly, but I now have dBASE IV 1.5.  What I no
longer have is the information on how to configure it to work with
extended ASCII French language text.

I would be very grateful if that programmer (or anyone else) could
give me a hand with this problem.

Apologies all around for having been so careless with my mail...

   Nicholas Hawes
   Acadian Archives/Archives acadiennes
   University of Maine at Fort Kent
   Fort Kent, ME 04704
   hawes@maine.maine.edu
Newsgroups: comp.databases
From: cortes@enuxva.eas.asu.edu (Enrique Cortes-Rello)
Subject: simple SQL dbms for MS-DOS
Organization: Arizona State University
Date: Tue, 5 Jan 1993 18:11:57 GMT

Hi,

I will be teaching a short database seminar in 
Bolivia, and I am looking for a cheap
(or FREE!) SQL-DBMS for instructional
purposes. Said seminar would be useless
without some hands-on experience for the
participants. 

Unfortunately, my hosts don't have a DBMS to
play with. 

It seems that the host university has 
MS-DOS machines only (I am not sure if
they have windows).

Any pointers will be appreciated!

ENRIQUE

---------------------------------------------------------
     Enrique Cortes-Rello  <cortes@asuvax.eas.asu.edu>
         ASU Intelligent Information Systems Lab
      <<<  "Aprendiz de todo, oficial de nada"  >>>
Newsgroups: comp.databases,biz.comp.software,comp.sources.wanted,comp.text.desktop
From: fitzgb@mml0.meche.rpi.edu (Brian Fitzgerald)
Subject: catalog publishing software wanted
Followup-To: comp.databases
Organization: Rensselaer Polytechnic Institute, Troy, NY
Date: Sat, 9 Jan 1993 03:54:57 GMT

Catalog publishing software wanted.

I'm looking for a program that can access a business database (say
Paradox), extract the stock number, price, and description, and produce
a publication quality merchandise catalog (justified, multicolumn, with
white boxes for pix desirable.)

If there is a _convenient_ way to do this by linking a word processor
to a database, I'm interested -- something a bit more sophisticated
than exporting/inporting ascii.  Stories about your own experiences,
good or bad, are welcome.

Information about add-ons to database programs, or complete business
packages, free or commercial, would be welcome.

Pointers to magazines or recent articles cover this subject would be
appreciated.

Thanks loads,

Brian

Followup to comp.databases, or any appropriate newsgroup, or e-mail.
From: jhagen@npri6.npri.com (Jarom Hagen)
Newsgroups: comp.databases
Subject: Recital Comments Requested
Date: 5 Jan 93 19:46:13 GMT
Organization: NPRI, Alexandria VA

I am looking at an evaluation copy of Recital for VMS and I
would like any comments you may have about Recital.

Also, if someone would inform me what I need to do to connect
to Rdb, I would be most grateful.

Thanks,

Jarom
-- 
-------------------------------------------------------------------------------
  *Not paid for and/or endorsed by NPRI.  602 Cameron St, Alexandria VA 22314
  (UUCP: ...uunet!uupsi!npri6!jhagen)       (Internet: jhagen@npri.com)
Newsgroups: comp.databases,comp.sources.d,comp.sources.wanted
From: stcsh@sninj.com
Subject: Berkley's ingres database - help
Date: Wed, 6 Jan 1993 19:30:57 GMT
Organization: SNI_New_Jersey
X-Newsreader: Tin 1.1 PL3


Hi,

I did bought the gnu tools on a cd. This cd contains the ingres
database, as well. However, I made a lot of changes in the source
code to compile it under Domain OS. I am not able to link the
commands. The file 'insert_mbtree.c' is missing in the distribution.
As well, at link time I get the following errors:

	symbol not found

	insert_mbtree  first ref...
	htons  first ref...
	Qbufsize  first ref...

I have the version 8.1 (version.h header file). I would appriciate
any kind of help to finish the port of ingres to Domain OS.

Steffen
From: jjast7+@pitt.edu (James   J Alles)
Newsgroups: comp.databases
Subject: Arev 3.02?
Date: 8 Jan 93 07:39:46 GMT
Article-I.D.: blue.1525
Organization: University of Pittsburgh (It's an Oxymoron thing)


Please clarify - I have 3.01 with patch #4.  Haven't seen 3.02 on
compu$erve.
-- 

Peace, JA
--
But Officer, my car doesn't GO that fast!  alles@med.pitt.edu
Newsgroups: comp.databases
From: labamba@sdf.lonestar.org (Peter Steiger)
Subject: Re: Looking for DBF & Clipper index format...
Organization: sdf public access Unix, Dallas -- 214-436-3281
Date: Mon, 11 Jan 1993 03:07:47 GMT

> I would like to know where I can find some documentation on the
> format of DBase3++ files.  Furthermore, and here's the *real*
> wish-list part, I need to know enough information to access
> Clipper index files (.NTX).

Jon,

Six months ago, you would have been out of luck, but as I understand it,
the new Clipper release will provide MUCH more information about file structures
for the sake of Replaceable Database Driver vendors.  For the time being, though, good luck.


One company, SuccessWare, wanted to write an improved index driver for Clipper
and requested information on the database/index format.  They were stonewalled
and eventually had to reverse-engineer the work themselves.  The result was
an INCREDIBLE improvement (they followed FoxPro's index format, which is much
more efficient).  This little anecdote doesn't help you much, but explains
how hard it is to get .NTX information from CA (formerly Nantucket).

Why do you need to have low-level file layouts?  Your best bet would be to
write your export routine in Clipper (or Fox, or Force...), compile it into
an .EXE, and call it from your mailmerge application.  Or am I missing something?

As for recommended libraries, I can't give enough praise to Successware's
DBFSIX driver.  Among other things, it provides Foxpro-compatible index files,
lets you store multiple index keys in one file (the "condensed" index),
and has optimized queries (the "mach six" driver).  Who knows--- maybe they'd
even be more cooperative about low-level file formats, after all they went
through!
From: sbk@ebt.com (Bobby Koritala)
Newsgroups: comp.databases
Subject: Querying in a Hierarchical Database
Keywords: SQL, SFQL, Hierarchical, Database
Date: 6 Jan 93 20:27:33 GMT
Organization: Electronic Book Technologies, Inc.

Hi

I was wondering if anyone out there has information regarding querying in
hierarchical databases. 
I am particularly interested in performance studies involving queries in 
SQL and/or SFQL (Structured Full-Text Query Language) on hierarchical data
modified into a relational form. References to literature are welcome.
Thanks.

Bobby S. Koritala

Newsgroups: comp.databases
From: af458@yfn.ysu.edu (Jon K. Salmon)
Subject: Looking for DBF & Clipper index format...
Organization: Youngstown State University/Youngstown Free-Net
Date: Fri, 8 Jan 1993 02:48:56 GMT


Netheads,

I would like to know where I can find some documentation on the
format of DBase3++ files.  Furthermore, and here's the *real*
wish-list part, I need to know enough information to access
Clipper index files (.NTX).

I would appreciate any of the following:

  * better choices of lists to post this request

  * ftp sites, preferably with a path or filespec specified

  * recommended commercial libraries

As for background, I am working on a WordPerfect 3rd Party
Interface and need to access various DBase3++ database files
and Clipper index files.  The databases (and indexes) are
maintained by a dedicated PC running a Clipper application;
thus, the databases and indexes WILL be open and in use by
this dedicated system at the same time I need to access them
from a remote workstation (Token ring Novell 3.11 by the way).
On the positive side, I only need READ access to the files.
The program is being written in C++ and assembly.  Oh, one
further limititation: because of the nature of the WP 3rd Party
interface and other resident programs in the work environment,
the program can only be roughly 70k resident.  Thus, any 3rd
party libraries which increase my code/data size substantially
are not feasible.

Thanks!

-- Jon
--
From: don@duncan (Don Radvan)
Newsgroups: comp.databases
Subject: Hierarchical Structures in RDBMS
Keywords: hierarchical
Date: 6 Jan 93 09:43:40 GMT
Organization: Devon Systems International


I have an interesting problem. I need to represent hierarchical data  
structures within a relational db, but I need to do it in a way that  
permits the user to create his own hierarchy. That is, I do not know the  
structure of the hierarchy before hand. 

For example:
	A user wants to organize various objects. These objects will  
appear as leaf nodes in the user's own hierarchy. The user may choose many  
different ways of organizing these objects, indeed, s/he may have many  
simultaneous hierarchies of organization for each set of objects. What  
results is a sort of directory tree. Each directory is a category of  
objects and each "file" or non-directory entry in a directory is an  
object. Given the objects of apples and oranges, we may get the following:

                                  Stuff
                                    |
                    --------------------------------
                  Food                          Non-Food
                    |
            ---------------------- . . .
         Fruit        Veggies 
           |
     -------------
  Apples       Oranges

And so when s/he does a query such as the following:
	select name where Food = "Fruit"
or
	select name where Stuff = "Food" AND Food = "Fruit"

we would get Apples and Oranges.

Any thoughts would be appreciated. Please reply by email.

--
  Don Radvan           #  Devon Systems International                 
  +44 071 499 8381     #  14 Old Park Lane                   Wedding Bells
  don@devon.co.uk      #  London W1Y 3LH     UK                in March  
  NeXTmail friendly    #              "Betwixt Hyde and Green"
Newsgroups: comp.databases
Subject: Re: Arev 3.01
From: D.M.Todd@massey.ac.nz (D.M. Todd)
Date: Mon, 11 Jan 93 03:57:09 GMT
Organization: Massey University, Palmerston North, New Zealand
Keywords: Revelation system variables
Summary: Couple of questions
X-Reader: NETNEWS/PC Version 2c

I would also appreciate more detail on the use of
push.session/pop.session, though I believe you do have to declare
these system subroutines (or call them) the way you would MSG or
anything else.  I'm missing something about how they are used and how
it is any better than just savinmg system values off to various
internal variable names.  An example would be a great help.

Thanks.

David
From: fun@gorgias.umdc.umu.se (Umea Young Scientists)
Newsgroups: comp.databases
Subject: 4 GL or what?
Date: 9 Jan 93 15:02:29 GMT
Distribution: comp
Organization: UMDAC, Umea, Sverige

Is there any other way writing apps for Btrieve-databases (using Btrieve
or NetWare SQL) than using traditional 3 GL languages (C, Pascal), is there
some language like that for Paradox (PAL)?

Please do answer to anders@bc.se since this isnt my account.

/Anders
Newsgroups: comp.databases
From: chau@ift.ulaval.ca (Nam Chau)
Subject: sql
Reply-To: chau@ift.ulaval.ca
Organization: Dept. Informatique, Universite Laval
Date: Mon, 4 Jan 1993 22:08:28 GMT

Can anyone tell me where to find the code source of SQL ?

Thanks a lot!

Nam Chau
Email:Chau@ift.ulaval.ca


Newsgroups: comp.databases