NoSQL

[NoSQL]

A Relational Database Management System

Carlo Strozzi

Italian Linux Society.

December 14th, 1998


NoSQL is a fast, portable, relational database management system without arbitrary limits, (other than memory and processor speed) that runs under, and interacts with, the UNIX Operating System. It uses the Operator/Stream DBMS paradigm described in "Unix Review", March, 1991, page 24, entitled "A 4GL Language". There are a number of "operators" that each perform a unique function on the data. The "stream" is suplied by the UNIX Input/Output redirection mechanism. Therefore each operator processes some data and then passes it along to the next operator via the UNIX pipe function. This is very efficient as UNIX pipes are implemented in memory. NoSQL is compliant with the "Relational Model".

Table of Contents


Copyright

NoSQL RDBMS, Copyright (C) 1998 Carlo Strozzi. Part of NoSQL code comes from RDB, a similar package written by W.Hobbs, an has been included in NoSQL with permission from the author.

NoSQL comes with ABSOLUTELY NO WARRANTY; for details refer to the GNU General Public License.


What is NoSQL

NoSQL, which I personally like to pronounce noseequel, is a derivative of the RDB DataBase system. The latter was developed at RAND Organization by Walter W. Hobbs. The few Perl scripts included with NoSQL are still very close the original RDB ones, so a good share of the credit for them goes to the original author.

Other major contributors to the original RDB system, besides W. Hobbs, were:

Chuck Bush

Don Emerson

Judy Lender

Roy Gates Rae Starr

People who helped with turning RDB into NoSQL:

Vincenzo (Vicky) Belloli

David Frey

Giuseppe Paterṇ

Maurizio (Masar) Sartori

The NoSQL.jpeg logo has been kindly provided by Kyle Hart.

As its name implies, NoSQL is not an SQL database, but rather a shell-level tool. The rationale behind it is well explained in the accompanying paper "The UNIX Shell As a Fourth Generation Language", available in both Postscript and ASCII format.

The data is contained in regular UNIX ASCII files, and so can be manipulated by regular UNIX utilities, e.g. ls, wc, mv, cp, cat, more, less, editors like 'vi', head, RCS, etc.

The form of each file of data is that of a relation, or table, with rows and columns of information.

To extract information, a file of data is fed to one or more "operators" via the UNIX Input/Output redirection mechanism.

There are also programs to generate, modify, and validate the data. A more through discussion of why this type of relational database structure makes sense is found in the book, "UNIX Relational Database Management", Reference #2.

To use NoSQL, it is assumed that the user has at least a minimum knowledge of the UNIX Operating System, including knowledge of Input/Outout redirection (e.g., STDIN, STDOUT, pipes).

NoSQL tends to be biased in favour of Linux. This means that, wherever it matters, NoSQL makes use of the GNU versions of the various UNIX commands, as those are the ones normally found on this UNIX workalike. NoSQL is Free Software, released under the terms of the GNU General Public License. As such, it fully qualifies as Open Source Software.


Why NoSQL

A good question one could ask is "With all the relational database management systems available today, why do we need another one ?". The main reasons are:

  1. Several times I have found myself writing applications that needed to rely upon simple database management tasks. Most commercial database products are often too costly and too feature-packed to encourage casual use. There is also plenty of good freeware databases around, but they too tend to provide far more that I need most of the times, and they too lack the shell-level approach of NoSQL. Admittedly, having been written mostly with interpretive languages (Shell, Perl, AWK), NoSQL is not the fastest DBMS of all, at least not always (a lot depends on the application).
  2. NoSQL is easy to use by non-computer people. The concept is straight forward and logical. To select rows of data, the 'row' operator is used; to select columns of data, the 'column' operator is used.
  3. The data is highly portable to and from other types of machines, like Macintoshes or MSDOS computers.
  4. The system should run on any UNIX machine (that has the PERL and the AWK Programming Languages installed).
  5. NoSQL essentially has no arbitrary limits, and can work where other products can't. For example there is no limit on data field size, the number of columns, or file size (the number of columns in a table may actually be limited to 32.768 by some implementations of the AWK interpreter, including mawk I think).

Again, the key feature of NoSQL (and other similar packages mentioned in this manual), is its close integration with UNIX. Unlike other fourth generation systems, NoSQL is an extension of the UNIX environment, making available the full power of UNIX during application development and usage. This level of integration removes the need to learn yet another set of commands to use and administer the database system. A database is just a file, and can be maintained like all other files that the user owns or has access to. Because NoSQL commands are executable programs, the UNIX shell is inherited as the primary command language of the database; no other proprietary database scripting language, to my knowledge, is as powerful and flexible as the UNIX shell. The shell-level nature of NoSQL encourages casual use of the system, and succesful casual use leads to familiarity and succesful formal use. This concept is much more thoroughly explained in the aforementioned paper "The UNIX Shell As a Fourth Generation Language", that shows why the UNIX shell is an excellent tool for scripting database access.


How to get NoSQL

NoSQL can be freely downloaded from the main FTP site ftp://ftp.linux.it/pub/database/NoSQL .


Support

There is a mailing list for discussions related to NoSQL. The address is noseequel@uu.ml.org. To subscribe simply send a message to noseequel-request@uu.ml.org with the word "subscribe" (without the quotes) in the message body.


References

  1. "Unix Review" magazine, March, 1991, page 24, "A 4GL Language".
  2. "UNIX Relational Database Management", R. Manis, E. Schaffer, R. Jorgensen, 1988, Prentice Hall.
  3. "The AWK Programming Language", Aho, Alfred V. and Kernighan, 1988, Addison-Wesley.
  4. "Programming PERL", L. Wall, R. Schwartz, 1991, O'Reilly & Associates.
  5. "UNIX Shell Programming", L.J. Arthur, T. Burns, 1997, John Wiley & Sons.