| T.R | Title | User | Personal
Name | Date | Lines |
|---|
| 294.1 | Nixdorf's DDB4 Info. | MSAM00::ZAHIRYUSOF | | Mon Mar 12 1990 04:59 | 152 |
| Hi,
I just noticed this note and I'm not sure whether you still need this.
Anyways, I think I just put it in here in case there is still others
that will be interested in this information.
Product name : DDB/4 or RDS (Relational Database System).
Formerly known as REFLEX which they have to drop the name as there is
an existing product by that name.
Features of DDB/4 or RDS on Targon (UNIX) :
1) Logical data independence.
New tables and column can be added to the database without the
need to modify existing application programs or reorganize the
database.
"It's normal for any relational database, nothing that Rdb cannot
do."
2) Virtual tables.
User can select or extract lines or columns from existing tables
to form a new, virtual table (logical view).
"Again this is normal for any relational database."
3) Dynamic growth of database.
The size of the database is automatically expanded as new data is
added. There is no need to specifically allocate disk space.
"This is also available in Rdb/VMS. "
4) The database system checks the data entered into the database for
compatibility with the field type and validity with respect to
defined value range.
"This is like VALID IF and CONSTRAINT in Rdb/VMS."
5) Consistency.
Only when a transaction can be successfully executed will the
changes be actually reflected in the database.
"This is the same as using COMMIT and ROLLBACK in Rdb/VMS."
6) Access Control.
Data is protected from unauthorized access and modification by
assigning user-specific privileges.
"Rdb/VMS probably has a better security scheme."
7) Accelerated Access.
Any data may be accesed via any column that is using the access
trees created with any desired columns.
"This is like B-tree index in Rdb/VMS. However we have extra features
i.e Hash Index."
8) Copies of data in the computer network.
"Rdb/VMS complement this using Vax Data Distributer - probably does
it even better. "
9) Database buffer.
The access time to information held in the database is optimized
thru a buffer pool.
" Same feature as the buffer pool in Rdb/VMS."
10) Concurrent operation of the database process serving the users.
"Snapshot file facility in Rdb/VMS - feature is the same."
11) SQL language interface.
SQL can be used both in application program and by end user.
"Vax SQL is better anyways theirs have more non -ANSI commands which
means it will not be portable."
12) Pre compilation of Application.
Database application programs are are pre compiled thus
eleminating time- consuming interpreting at run-time.
"Rdb/VMS also has precompilers."
13) RDS-SQL.
The interactive database component RDS-Query after a command
interface at terminal.
"Rdb/VMS also has the interactive SQL utility."
14) RDS-Easy.
Provides end user with a tool which generates standard forms for
each database table.
"Something like datatrieve is more powerful."
15) RDS-Load.
Selected data from RDS table may be stored in files and also may
be loaded from a file into the database.
"Rdb/VMS also has this capability."
16) RDS-Utility.
For administrative purpose, to use for controlling, configuring
and back up of database.
"Rdb/VMS has stronger utility for maintenance and control. Such as on
line/Incremental Backup."
17) RDS Dialogue Language.
A 4GL for programmer to handle simple data base applications.
"RALLY for us."
So, what Nixdorf RDS or DDB/4 does not have is the following :
1) Capability to create multifile database in which it will be useful
for tuning.
2) Online/Incremental Backup.
3) Sophisticated Performance and monitoring tool.
4) Hash indexing which will help in performance.
5) 3rd Party tools that will interface to the database.
6) Internatinalization, Triggers, Changing characteristics of
database while other users are still active on the database which
is in Rdb/VMS v3.1 is not present in DDB/4.
7) Interface to DB2.
8) Interface of database to PC or workstations.
9) Eventhough DDB means distributed dataBase but it is not a true
distributed database as it does not have 2-phase commit. This
feature will be available in Rdb/VMS v4.0 next year.
10) AIJ file use for automatic recovery in Rdb is not present in
DDB/4.
Nixdorf also has DDB/4 for their MCS and 8860 (DIPOSS). However, it
has a lot of maintenance problems such as Backup, Restore, Extraction
of data and data integrity itself. I'm beginning to wonder now whether
they have fixed all these problems. Currently the strategy is to market
DDB/4 running on Targon rather than on 8860.
By the way, Oracle can run on Targon - believe it or not !!!
Zahir.
|
| 294.2 | Guesses about OSF | WIBBIN::NOYCE | Bill Noyce, FORTRAN/PARALLEL | Mon Mar 12 1990 15:16 | 12 |
| Re .0:
>> The customer also said that
>> this product has been selected by OSF to become THE standard database
>> product. Is it true ?
OSF has selected a bunch of standards to represent the "Application
Environment". These include ANSI FORTRAN, ANSI C, etc. Not too
surprisingly, the database standard they chose is ANSI SQL. Perhaps
this is what the customer means. I'd be surprised to hear that
OSF has selected a specific *product* to be the standard database;
users who confine themselves to the ANSI SQL language should be
able to write code that runs on a wide variety of database products.
|
| 294.3 | OSF Information is INCORRECT | COOKIE::BERENSON | Words are a deadly weapon | Mon Mar 12 1990 21:32 | 14 |
| In the original announcement of the founding of OSF they stated that they would
be pulling together technology from multiple companies; that IBM was
contributing AIX; Digital DECwindows; etc. etc. etc. and Nixdorf its database
technology.
The reality of how OSF works is that it sents out an RFT - Request for
Technology - and then chooses from the submissions. In the case of windowin
technology they did not choose DECwindows per se, but instead combined
some aspects of DECwindows and some from HP to create OSF/Motif.
No RFT for a database system has been issued, and the only one anticipated is
for INTEROPERABILITY not the database system itself.
Your customer is just plain wrong, having been mislead by the original announcement.
|
| 294.4 | DDB4 is no longer owned by Nixdorf | COOKIE::MELTON | The zen of character sets | Mon Mar 26 1990 00:05 | 15 |
| In addition to the comments Hal made in .3, I'd like to point out that
Nixdorf no longer owns the software development group that is developing
DDB4. The group was spun off into a separate corporation (still partially
or mostly owned by Nixdorf, however) that may be bought into by Cincom
(according to the rumor mill).
Apparently, DDB4 development has run into significant problems; I *think*
that these are financial, rather than technical, in nature, but don't have
direct information.
X/Open no longer even bothers to track DDB4 as an interesting database
product (mostly because Nixdorf is the X/Open member, not the spinoff).
Regards,
Jim
|
| 294.5 | DDB4 on Other O/S ? | MSAM00::ZAHIRYUSOF | | Sun Apr 08 1990 11:17 | 7 |
| Somebody in the Nixdorf Management had mentioned in a local Computer
Newspaper that DDB4 not only runs on UNIX but other operating systems
such as MVS, OS/2, MS-DOS and VMS ?? Is this really true ?
Rgds,
Zahir.
|