oracle vs mysql 
after fiddling with mysql a bit, you normally want to use a real database. The limitations of mysql are numerous: no views, no triggers, no stored procedures and so on. For very simple applications its ok, but sql is more than just a select statement. Therefore someday you move over to oracle. Oracle software normally sucks, but their sql server rocks. Its very stable, scalable, unix oriented stuff.

Some do's and don'ts:
- never run oracle on windows. Its not stable (even less stable than windows itself). It is just not a good combination. You need to reboot it all the time (at least daily) due to memory leaks. Prepare for the worst if you're following this path.

- Never use other oracle software than their database server. Oracle forms? a joke. Oracle designer? sucks. Oracle installations: Always a pain. I have *NEVER* seen an oracle installation procedure without severe errors. (and that means over 7 years of oracle installtion history)

- Oracle databases are memory hungry. Start with 1Gb, then go up.

- After install, immediately tune up the server parameters. The defaults are not usable. Make your shared pool at least 500M for a 1Gb server, use large dbblocks (16k at least) If you don't do this, only 2 users can log in

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mysql from a remote machine. 
Assuming you can connect locally to mysql, you'd expect to be able to connect remote...not! This is not as easy as it seems.

First make sure you CAN access the mysql server from a remote machine. By default, the my.cnf file contains a statement:
bind-address=127.0.0.1
that is in your way. This only allows connections from the localhost. Put a # in front of it.

After this, still no luck, because the mysql privilege system is not your default user/password pair, but mysql for some reason also needs to know where you're calling from. This is due to the unusual non-standard structure of their user table: it contains host/user/password.

So add your remote host to the table by issuing:

grant all on *.* to user@remotehost identified by 'password'

or, if you want to allow access from all hosts, use a % like:
grant all on *.* to 'user'@'%' identified by 'password'

note: put quotes around username and host if neccesary. Beware not to quote the complete thing (like 'user@host') because mysql thinks you mean user "user@host" on the local machine.

Because mysql caches privileges, you need to flush them so enter:
flush privileges

after this you should be able to login

to see if its ok, do

use mysql
select * from user;

That's it. Sounds easy, but as the mysql documentation index/search sucks bigtime it can take you hours to find this out. (for instance, searching on the 1130 error number puts you on the wrong trail by giving information about blocked-hosts that has nothing to do with the real problem)



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Gentoo and the pvr350 with ivtv support 
Getting mythtv to work is the final step in a long range of sub-applications that need to work first. Amongst these are:

Mysql
One is mysql. Emerge mysql does the trick, but then
/etc/init.d/mysql start
told me that I still needed to run a script. The ebuild doesn't do this for you. After this the mysql server started, and running the client (also called mysql) with the simple test command 'show databases' showed everything was fine.

Ivtv
For the pvr350 (or pvr250 card) you'll need ivtv (http://ivtv.sourceforge.net). So first
emerge ivtv
Getting the pvr350 card to work needed some tweaking as well. The "default" kernel doesn't add tuner.o in the modules directory. Reason is that the BT848 is not included as a module. Reason for this is that the i2c bit-banging interfaces are OFF. These deep-dependancies can be a pain in the ass.

to fix this:
genkernel --menuconfig all
Then when the menuconfig screen appears, i went to character devices->i2c support
turned the bit-banging interface.
Then to the multimedia video section and turned the BT848

To load the whole ivtv section during boot, i did
echo ivtv >>/etc/modules.autoload.d/kernel-2.4

Also some settings in the modules.conf are needed, but in gentoo you normally generate this file and put stuff in /etc/modules.d
After emerging ivtv, the file ivtv is already in /etc/modules.d, but it needs some tweaking.

Using modprobe tveeprom, found out that my tuner is type 5, so:
#alias char-major-61 lirc_i2c
#add above ivtv lirc_dev lirc_i2c
alias char-major-81 videodev
alias char-major-81-0 ivtv
### modprobe tveeprom geeft: tuner=philips FM1216 idx=21 type=5
options ivtv debug=1 ivtv_pal=1 tuner=5
options tuner pal=1 type=5
options saa7127 enable_output=1 output_select=0 pal=1
options msp3400 once=1 simple=1
add below ivtv msp3400 saa7115 saa7127 tuner
# add above ivtv lirc_dev lirc_i2c
# add above ivtv ivtv-fb
post-install ivtv /usr/local/bin/test_ioctl -d /dev/video0 -u 0xff

lirc is not functioning now, so that has to be done later on.

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The Via Epia M10000 with Nehemiah cpu 
Great stuff coming from via nowadays. I am experimenting with those via boards for a while now, and they are fun! Why buy a noisy, expensive 3Ghz intel or athlon, when all you need is a 600Mhz pc. On top of that, it does not need a fan, so it's completely silent.

Tutuut
One of the boards are build into a cubid case, which is about the size of a car radio. I am preparing this one to be used in the car. (the cubid has an external adapter on 12volts and an internal dc-dc converter into atx and disk voltage levels) This is the first epia project. It uses a M6000 epia board, and the thing is called tutuut. Main goal is a 160Gb car mp3 jukebox, but watching divx in the car would be nice too) Tutuut is currently running redhat8, but will be converted to gentoo or fedora core2 soon. Specs:
EPIA M6000 600Mhz cpu (fanless)
256Mb ram
160G seagate disc (seagate discs are very silent!)
Cubid 3688 case, 12volt input, dc-dc converter on board, fanless.
The cubid case does not support 3.5" harddiscs out of the box, but with a little effort it fits.



Montevideo
The other board is an epia M10000. It is build into a travla C137 case, which makes this a perfect fit as a tv-settopbox. A bit larger than the cubid case, but it supports one pci-slot with a pci-riser/corner card. The pci card in this case is a hauppauge pvr350, as this should be a linux-tivo box. It and has the option for a 3.5"harddisc standard (without drilling holes..) .
This machine is called montevideo, and is supposed to run mythtv (www.mythtv.org) , as this seems to be the best free tivo system at the moment. (in comparison with freevo, the other contender). The microsoft multimedia centre is not considered, as anything running on windows needs a 6Ghz processor to start with, and they cannot be bought as yet.

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getting the gentoo live-cd to work 
The gentoo manuals are great, taking you step-by-step through the whole process. Following this, i first needed their live-cd for booting this old pentium 166mhz. So i burned the live-cd 2004.2 iso (the minimal one).

Watch out that you burn this one as an 'image', so do not create a cd with the iso file on it as this does not work: you need to have a bootable cd. I used nero with the 'burn image' menu option. Just select the iso file and go.

With the freshly made cd I tried booting the old pentium system. It did not boot. So, was the bios set correctly? yes: bootorder CDROM,A,C That was not the issue. Maybe the cdrom was too old and dusty.. after all, the system was 8 years old. So I installed another cdrom in the system. no luck, but I found out that a fedora or redhat boot cd DID boot! So there is something wrong with the gentoo disc, as it does not boot in older systems. I made 5 copies of the CD just to be sure, but none of them would boot the old machine.

UPDATE: I did a gentoo install using the fedora boot disk - just boot the fedora boot cd in 'rescue' mode and start installing gentoo the moment the bash prompt is shown. Googling for other gentoo installtion info, I found out that knoppix (linux-on-a-cd) is also a good way of starting the gentoo installation, and maybe toms bootroot (linux-on-a-floppy, http://www.toms.net/rb/) might work for the older (386 and like) pc's, although I did not try this (yet!).

UPDATE2: There is a new experimental minimal-cd available which fixes this problem.

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