I have a heavy-used website powered by LAMP stack (CentOS Linux,
Apache 2, MySQL and PHP). It started on a shared hosting so I had to
use MySQL. Year and a half later, I switched shared, virtual hosting
and not run it on a dedicated server. I decided to try Firebird to see
how it performs and also how it compares to MySQL in RAM usage, disk
usage, etc.
The software
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The system is CentOS 5.5 64bit with default LAMP stack. I installed
Firebird 2.5. RC3 from the .rpm package on Firebird website.
Surprisingly, it does not require any additional rpm package 🙂
Converting the database
—————————–
As far as I can tell, there are no tools to do this automatically. I
created Firebird database and tables by hand, slightly editing the
schema dump from phpMyAdmin. This was easy. Loading the data seemed a
problem because default mysqldump places multiple VALUES clasuses in
INSERT statements. I used a Postgres tool mysql2pgsql to convert the
file to a more usable form:
http://pgfoundry.org/projects/mysql2pgsql/
I had to alter it a little bit, to avoid prefixing strings with E
character. I commented out this line:
#s/'((?:.*?(?:\\')?.*?)*)'([),])/E'$1'$2/g; # for the E'' see
http://www.postgresql.org/docs/8.2/interactive/release-8-1.html
Next problem was that ” and ‘ are escaped with backslash \.
With Firebird ” does not need escaping and ‘ is escaped with another
‘, becomes ”. A simple sed command to fix this:
cat postgres.sql | sed s1\\\\\"11g | sed s1\\\\\'1\'\'1g > firebird.sql
A few more manual edits were needed to remove the CREATE TABLE and
similar stuff, because I only needed data. After that I added
“commit;” to the end of the script and ran it via isql:
/opt/firebird/bin/isql /var/db/firebird/s.fdb -user sysdba -pass
******** -i firebird.sql
this took some time. Here is the result:
# du -h -s /var/lib/mysql/slagalica/
1.9G /var/lib/mysql/slagalica/
# du -h -s /var/db/firebird/slagalica.fdb
2.1G /var/db/firebird/slagalica.fdb
This is before I created indexed on tables in Firebird database.
Afterwards we get:
2.3G /var/db/firebird/slagalica.fdb
So, Firebird database is slightly bigger.
Now, it's time to convert the DB access layer in PHP application, and
compare the perfomance. Stay tuned...
