Free relational database software for linux

Firebird is a relational database offering many ANSI SQL-99 features that runs on Linux, Windows, and a variety of Unix platforms.

Firebird offers excellent concurrency, high performance, and powerful language support for stored procedures and triggers. Firebird Relational Database has been used in production systems and under a variety of names since 1981.

Firebird is a commercially independent project of C and C++ programmers, technical advisors and supporters developing and enhancing a multi-platform relational database management system based on the source code released by Inprise Corp (now known as Borland Software Corp) on 25 July, 2000 under the InterBase Public License v.1.0.


New code modules added to Firebird are licensed under the Initial Developers Public License. (IDPL). The original modules released by Inprise are licensed under the InterBase Public License v.1.0. Both licences are modified versions of the Mozilla Public License v.1.1.

Installing:

In order to install the firebird version of IB 6.0 you will need to perform the following steps:

1. Get the required packages:

Get the glibc update from RedHat, the one I used
was from ftp://updates.redhat.com/7.0/i386/glibc-2.2-5.i386.rpm

Get ncurses4 from
ftp://carrier.ision.net/pub/ftp.redhat.com/i386/en/RedHat/RPMS/ncurses4-5.0-2.i386.rpm
or another redhat mirror.

Get Firebird from
ftp://firebird.sourceforge.net/pub/firebird/release/FirebirdSS-0.9-1.i386.rpm

2. Prepare the installation:

Log in as root.
Use a plain text console to do this and be sure
that all Gnome desktops are closed.
(One user reported that the Gnome desktop
(apparently ICEwm)
blocked port 3050. I could not reproduce this
here, but it seems that it uses port numbers
that arent assigned in /etc/services for own
purposes)

3. Add localhost.localdomain to /etc/hosts.equiv:
echo localhost.localdomain >>/etc/hosts.equiv

4. Change to the directory where you have placed
the downloaded packages.

5. Install the glibc update:
rpm --install --force glibc-2.2-5.i386.rpm

6. Install libncurses.so.4:
rpm --install --force ncurses4-5.0-2.i386.rpm

7. Install Firebird:
rpm --install --force FirebirdSS-0.9-1.i386.rpm

8. Add /opt/interbase/bin to your path:
You can either change /etc/profile
or do
export PATH=$PATH: /opt/interbase/bin
or
change the profiles in your users home directories

9. Check that all went well:

Read /opt/interbase/SYSDBA.password
to get your SYSDBA password.

gsec -display
should display the list of known users
(SYSDBA only after a fresh install)

isql /opt/interbase/examples/employee.gdb
SQL> SHOW TABLES;
should display all tables from this database
SQL>quit;

Mckoi SQL Database is a full featured SQL-92 relational database management system written in Java.

The software can operate as either a dedicated multi-client, multi-threaded database server, or can be used as an embedded database inside a Java application.

The engine is designed to be easy to use and maintain and versatile for sophisticated database development tasks. The software provides a JDBC 2.0 driver.

To use Mckoi SQL Database, you will need a JavaTM runtime environment version 1.2 or greater. Sun provides Java runtimes for Win32, Solaris and Linux from their website at http://www.javasoft.com/j2se/. IBM also provides various Java runtimes for a number of platforms at http://www.ibm.com/java/jdk/download/.

When Java has been installed on your system, unpack the mckoi distribution file to a directory in your file system. Then you are ready to create a database and develop your database application.

Creating A Database

Before you can begin development of your database application, you will need to create and configure a blank database. The database configuration file describes all of the configurable properties of the database (details of the database configuration file are covered in the next section). The software ships with a default configuration that looks for a database at path ./data in your filesystem.

To create a database using the default configuration with an admin username of admin_user and password aupass00, go to a prompt, change to the Mckoi Database distribution directory and type:

java -jar mckoidb.jar -create "admin_user" "aupass00"

We do not advise using either this username or password in a production system. The user created here has full control over every aspect of the database so choose a username / password carefully.

When the command has completed, a sub-directory called data will have been generated. This directory is used to store data from the database. A sub-directory called log is also generated which stores debugging and query log information.

Database Configuration

When you run the mckoidb.jar package, it looks for a file named db.conf in the current directory. This file contains a number of variables that determine where the database looks for information, as well as other user-definable properties. The configuration file can be renamed and copied to a different location. If you change the configuration file location, you must supply the location when you run the database;

java -jar mckoidb.jar -conf [location of conf file] .....

You can edit the configuration file with a text editor. The default configuration file that ships with the software contains extensive comments on what each variable does.

Haskell Database Connectivity project provides an abstraction layer between Haskell programs and SQL relational databases. This lets you write database code once, in Haskell, and have it work with any number of backend SQL databases (MySQL, Oracle, PostgreSQL, ODBC-compliant databases, etc.)
HDBC is modeled loosely on Perls DBI interface http://search.cpan.org/~timb/DBI/DBI.pm, though it has also been influenced by Pythons DB-API v2, JDBC in Java, and HSQL in Haskell.
HDBC is a from-scratch effort. It is not a reimplementation of HSQL, though its purpose is the same.
Main features:
- Ability to use replacable parameters to let one query be executed multiple times (eliminates the need for an escape function)
- Ability to access returned rows by column number
- Ability to read data from the SQL server on-demand rather than reading the entire result set up front
- HUnit testsuite for each backend driver
- Well-defined standard API and easy backend driver implementation
- Lazy reading of the entire result set (think hGetContents, but for the results of SELECT) (see sFetchAllRows)
- Support for translation between Haskell and SQL types
- Support for querying database server properties
- Add-on package (hdbc-missingh) to integrate with MissingH, providing a database backend for AnyDBM.
- Support for querying metadata such as column names.
- Support for querying additional metadata (column types, etc.)

GNUstep Database Library 2 (GDL2) is a set of libraries to map Objective-C objects to rows of relational database management systems (RDBMS).
GNUstep Database Library 2 aims to be compatible with Enterprise Objects Framework (EOF) as released with WebObjects 4.5 from Apple Inc.
Main features:
- EOControl (gnustep-db2control)
- The fundamental abstraction library which includes many non RDBMS related extensions such as KeyValueCoding extensions and other categories. Most importantly it contains the classes which handle the coordination of object graphs namely EOEditingContext.
- EOAccess (gnustep-db2)
- This library implements the underlying mechanism to retrieve and store data in RDBMS. It defines the abstract classes like EOAdaptor which are subclassed to interface with concrete RDBMS implementations.
- EOInterface
- This library implements classes used to synchronize UI components such as NSTextFields, NSButtons and NSTableViews with the state of objects which an EOEditingContext contains.
- EOAdaptors
- This is a collection of concrete EOAdaptor projects needed to connect to specific databases. GDL2 currently only supplies an Adaptor for the PostgreSQL database. Even though the Adaptor is still called Postgres95 we aim to support PostgreSQL 7.2 and higher API. In fact the Adaptor may very soon be renamed to PostgreSQL.
- DBModeler

KInterbasDB project is a Python extension package that implements Python Database API 2.0-compliant support for the open source relational database Firebird and some versions of its proprietary cousin Borland Interbase.
In addition to the minimal feature set of the standard Python DB API, KInterbasDB also exposes nearly the entire native client API of the database engine.
Enhancements:
- At concurrency_level 1, it was possible for a deadlock to occur if KInterbasDB simultaneously raised an exception in one thread while executing a SQL statement in another. This problem did not affect concurrency_level 2. Thanks for Atsuo Ishimoto for reporting this bug.
- The official implementation of the automagic TEXT_UNICODE type translator (in the kinterbasdb.typeconv_text_unicode module) was missing support for the new character sets introduced in Firebird 2.0 (namely, the corrected version of UTF8, plus KOI8-R, KOI8-U, and WIN1258). Thanks to Oleg Deribas for bringing this to my attention.

ObjStore::Internals is a Perl module with a few notes on the implementation.

SYNOPSIS

You dont have to understand anything about the technical implementation. Just know that:

ObjectStore is outrageously powerful; sophisticated; and even over-engineered.

The perl interface is optimized to be fun and easy. Since ObjectStore is also blindingly fast, you can happily leave relational databases to collect dust on the bookshelf where they belong.

So basically, you dont have to understand anything to a greater depth. Its not necessary. Youve arrived. You will be successful. However, more detail follows. If you like to turn things inside-out, read on!


Perl & C++ APIs: Whats The Difference?

Most stuff should be roughly the same. The few exceptions have generally arisen because there was a perl way to make the interface more programmer friendly.

Transactions are perlified.

Some static methods sit directly under ObjStore:: instead of under their own classes. (Easier to import.)

Databases are always blessed according to your pleasure.
lookup, open, is_open, and lock_timeout are augmented with multi-color, pop-tart style interfaces.

Why not just store perl data with the usual perl structures?

CHANGE CONTROL

As perl evolves, new data layouts are introduced. These changes must not cause database compatibility problems.

BINARY COMPATIBILITY

Perl doesnt have to worry about binary compatibility between platforms. Databases do. In addition, databases impose a number of restrictions on persistent data layout that would be onerous and sub-optimal if adopted by perl.

MEMORY USAGE

Perl often trades memory for speed. This is the wrong trade for a database. Memory usage is much more of a concern when data sets can be as large or larger than ten million megabytes. A few percent difference in compactness can be quite noticable.

Yet Another Calendar is a malleable, clear, concise CGI calendar. Yet Another Calendar project doesnt require a relational database server and uses a single page per month for editing and viewing.
Main features:
- XML/RSS export
- Palm datebook (.pdb) export
- Text export (tab delimited file)
- Single page for editing and viewing
- Optional start and end times for all events
- Edit history/change tracking (with an rcs cron job)
- Archiving of old events (also with a cron job)
- Small amount of source code (under 500 lines)
Enhancements:
- There are now links on the calendar for an XML/RSS feed, a Palm datebook (.pdb) file, and a tab delimited text file.
- A few minor bugfixes and enhancements were made.

Dee-Python project is an implementation of a truly relational database language with Python. Inspired by Date and Darwens Third Manifesto, it addresses the problems of impedance mismatch between programming languages and databases and the weakness of SQL.

Mind The Gap

Most of todays programs handle data in one way or another and often this data is stored in some kind of relational database. To read and modify this data, a program must bridge the gap between its representation and the one used by the dialect of SQL that the database provides. This bridge typically comprises a database API that sends queries as text strings, often accompanied by some kind of table-to-object mapper that has to coerce data and relationships in both directions, usually with elaborate layers of abstraction in an effort to keep the two sides loosely coupled.

"Yet by obscuring the true data source these solutions end up throwing away the most compelling feature of relational databases; the ability for the data to be queried."

Microsoft, DLinq .NET Language-Integrated Query for Relational Data, May 2006.

This approach not only adds complexity and increases the need for data transformations but, most importantly, it destroys the significant advantages provided by the relational model of data. The relational model is built upon predicate logic which brings the power of formal reasoning to data: it is the only sound foundation available.