On Wed, Nov 25, 2009 at 3:42 PM, Manasi Save < manasi.s...@artificialmachines.com> wrote:
> Dear Johan, > > Need your help again in understanding How mysql reads symlink. > > As you said below, I have created symlinks in default mysql directory. > and try to read that symlink file as a database. But mysql is not reading > that file as Database. Is there any settings which I need to change. > Make sure the directory the symlink points to has the same owner, group and permissions as your other databases. The permissions of the symlink itself are irrelevant (at least, on a Linux system. YMMV for other *nixen). *mytest1:~# cd /var/lib/mysql mytest1:/var/lib/mysql# ls -lh* total 117M -rw-r--r-- 1 root root 0 2009-11-19 12:08 debian-5.0.flag -rw-rw---- 1 mysql mysql 106M 2009-11-25 11:53 ibdata1 -rw-rw---- 1 mysql mysql 5.0M 2009-11-25 11:53 ib_logfile0 -rw-rw---- 1 mysql mysql 5.0M 2009-11-25 11:53 ib_logfile1 drwxr-xr-x 2 mysql root 4.0K 2009-11-24 10:27 mysql -rw------- 1 root root 7 2009-11-19 12:08 mysql_upgrade_info drwx------ 2 mysql mysql 4.0K 2009-11-24 10:43 tmp *mytest1:/var/lib/mysql# mysql* Welcome to the MySQL monitor. Commands end with ; or \g. Your MySQL connection id is 690 Server version: 5.0.51a-24+lenny2 (Debian) Type 'help;' or '\h' for help. Type '\c' to clear the buffer. *mysql> show databases;* +--------------------+ | Database | +--------------------+ | information_schema | | mysql | | tmp | +--------------------+ 10 rows in set (0.13 sec) mysql> Bye *mytest1:/var/lib/mysql# mkdir /tmp/remotedatabase mytest1:/var/lib/mysql# chown mysql:mysql /tmp/remotedatabase mytest1:/var/lib/mysql# chmod u+rwX /tmp/remotedatabase mytest1:/var/lib/mysql# ln -s /tmp/remotedatabase ./ mytest1:/var/lib/mysql# mysql* Welcome to the MySQL monitor. Commands end with ; or \g. Your MySQL connection id is 691 Server version: 5.0.51a-24+lenny2 (Debian) Type 'help;' or '\h' for help. Type '\c' to clear the buffer. *mysql> show databases;* +--------------------+ | Database | +--------------------+ | information_schema | | mysql | | remotedatabase | | tmp | +--------------------+ 11 rows in set (0.01 sec) *mysql> use remotedatabase;* Database changed *mysql> create table a (a int);* Query OK, 0 rows affected (0.04 sec) *mysql> show tables;* +--------------------------+ | Tables_in_remotedatabase | +--------------------------+ | a | +--------------------------+ 1 row in set (0.01 sec) mysql> Bye mytest1:/var/lib/mysql# > > Thanks in advance. > > -- > Regards, > Manasi Save > Artificial Machines Pvt Ltd. > > > On Wed, Nov 25, 2009 at 11:55 AM, Manasi Save < > > manasi.s...@artificialmachines.com> wrote: > > > >> Hi Johan, > >> > >> I am Sorry. If I have complicated the senerio But, this still not fix my > >> purpose. > >> > >> What I want is - From your example :- > >> > >> /data/disk1/mysql/db1 (directory) > >> /db2 (directory) > >> /db3 (directory) > >> /db4 (symlink to /data/disk2/mysql/db4) > >> /db5 (symlink to /data/disk2/mysql/db5) > >> /db6 (symlink to /data/disk2/mysql/db6) > >> > >> I dont want to create these directories here (/data/disk1/mysql/d4 > >> /d5 > >> /d6). > > > > > > They're not directories, they're symlinks, which are (to the OS) a kind > of > > file, and thus not limited to 32000 per directory. They behave mostly > > identical to a directory, though, so MySQL will pick them up seamlessly, > > with the one hitch that you'll have to replace "create database" > > statements > > by mkdir and ln calls on the OS level. > > > > This is afaik the only way to do this on the MySQL level. It is > impossible > > to specify multiple base directories. > > > > Another possible option, but higher in complexity and most likely less > > performant, would be to run two instances of MySQL on different ports > with > > different data directories, and use MySQL Proxy to redirect incoming > > connections based on whatever criterion you could script into it - "use > > database" statements, for example. This is however going to come with > it's > > very own set of catches and limitations. > > > > I'm not big on proxy, myself, so I'm afraid if the symlink option is not > > acceptable to you, I can't help you any further. > > > > >
