February 2011


You get an approximate value by running gstat and then check out the
Data pages value for the table. Multiply that value with your database page size. This is the allocated space on disk.

From Milan Babuskov blog:

I decided to automate conversion of MySQL database to Firebird. I got tired of manual find&replace process, and created a small parser that changes from MySQL to Firebird syntax. Currently it only supports database structure dump (no data, only structure) from PHPMyAdmin. Not all datatypes are supported, but feel free to “fix” it. It’s written in PHP and it’s open source. It would be great if you would send back any modifications you make. Download it here (source code included).

In this tutorial I will show you how to install multiple separate Firebird 2.1 servers on a single Host

What is Asyncronous System Trap ? : This is similar to Unixes signal’s or OS interrupts.
Technically this is callbacks from Lock Manager into the Engine called when
somebody acquires lock at level not compatible with current level. In this case
all processes who owns the lock receives notification and should take appropriate
action to release lock (immediately or deferred-ASAP).

The main trick with AST’s handlers is that AST is send asynchronously and
handler must take care to work correctly. Since v2.5 all ATS handlers runs in
separate thread. Before v2.5 it works using signals on Unixes and threads on
Windows.

PS the issue with old glibc and FB 2.5 is that since v2.5 we abandoned usage of old
System V semaphores (do you remember “semaphores are exhausted” error ? now
you can forget it completely) and start to use pthread mutexes. And old glibc have a
bugs in pthread mutex implementation.

Related to previous announcement:If you are on ubuntu and your ubuntu release is greater than Hardy (8.04) you are safe , on other distributions you can determine this way the glibc version
You must run the /lib/libc.so.6 and it will return the glibc version
in the first row.
In ubuntu or any debian based distro

/lib/libc.so.6 | head -n 1
GNU C Library (Ubuntu EGLIBC 2.13-0ubuntu1) stable release version
2.13, by Roland McGrath et al.

in this case glibc is 2.13
and is builded from eglibc sources

https://launchpad.net/ubuntu/+source/eglibc

another option is dpkg interrogation

dpkg -l libc6

on rpm based distros

rpm -q glibc

ps: other alternative ways

From www.firebirdsql.org:

It has been found that V.2.5 Classic for Linux has problems with AST delivery if used with glibc 2.5. With glibc 2.7 it works properly. The situation with glibc 2.6 is unknown for now. If your glibc version is lower than v.2.7, it must be upgraded before using Firebird 2.5 Classic/Superclassic.

Web-based Squirrel SQL client. It allows you to view database structure, import/export and manage your databases, including create database, table, store procedure, view,trigger and user. it supports Firebird

So, you just moved to that new cool server, with lots of RAM, Windows and Firebird 64bits, but suddenly you found that Firebird performance gets worse and worse. When you check TaskMan, you see that 99% of the RAM is being used (and so, swap is going on). If you close Firebird process, RAM usage seems to be back to normal. Weird, uh?

First, you may think this is the common problem of Classic/SuperClassic with too many connections and crazy buffers value… but, you checked all the settings, and everything is ok.

If  this happening to you, take a look again in TaskMan (or Process Explorer), and check how much memory the OS Cache is consuming. If you find something abnormal, like if it is consuming almost all of your physical RAM, you should take a look at this: http://support.microsoft.com/kb/976618/en-us

On devshed firebird forum someone asked if anyone used SchemaSpy with firebird , and later he got it working , here is the command line option (after installing jaybird.jar)
1) Download the ZIP file for jaybird
2) unzip it
3) Copy the file jaybird-full-2.1.6.jar into a convenient directory
4) specify the full path to the .jar file when starting schema spy

java -jar /home/java/schemaSpy_5.0.0.jar -t firebird -db /var/lib/firebird/2.1/data/employee.fdb -s schema -u SYSDBA -p ******* -o /home/firebird/ -port 3050 -host localhost -dp /home/user/jaybird-full-2.1.6.jar

ps:that is a single line

here is the mention.

Istallation proved very easy, and intelligently chosen defaults allowed us simply to press ‘Next’ through most of the wizard. A Firebird database is provided

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