#755 Passing the database name at run time to DataBaseds.

[Franco Carbognani]

Hi,
here in Virgo we have the following specific Tango deployment:

• We have made an installation of Tango 9 (from sources) on a disk area shared by many Scientific Linux 6 (SL6) workstations.
• We are using a centralized mysql hosted by a dedicated server accessed remotely
• We are supporting more than one TANGO_HOST and corresponding database

Out of this setup rises the need to be able to run the same shared DataBaseds executable providing to it the name of a diffrent mysql database to connect to.
At the moment the database name is defined at "configure" time and the DataBaseds executable is bound to it.

We are then making a change request for allowing to pass the database name at run time to DataBaseds.

We have already made a possible implementation of such change request by introducing an environment variable MYSQL_DATABASE. We attach to this change request the corresponding patch file.

We have made few tests with this modified DataBaseds, running two instances of it pointing to two diffrent remote mysql databases and we have encountered no problem so far.

Thanks a lot

Franco, Giovanni and Luca

[Emmanuel Taurel]

Hello guys,

Thank's very much for the patch. I have applied it in the database and TAC server trunk. It will be part of next distrib. Note that I have applied a modified patch in order to get MYSQL_DATABASE value from a real environment variable or from the /etc/tangorc file (for Linux).

Have a nice week-end

Emmanuel

[Franco Carbognani]

How!
Thanks to you, Emmanuel, for your amazingly fast feedack.
And, sure, having MYSQL_DATABASE also set into /etc/tangorc is a good plus.

Cheers,

Franco

[Giovanni Cerretani]

The database name results to be still hard-coded in a procedure call in:

http://sourceforge.net/p/tango-cs/code/HEAD/tree/classes/cpp/dbase/trunk/DataBase.cpp#l7182

sql_query = "CALL tango.ds_start('" + svc + "','" + host + "'," + tmp_var_name + ")";

and this is preventing to use arbitrary database name, other than "tango", properly.

I've found "tango" hard-coded also in

https://sourceforge.net/p/tango-cs/code/HEAD/tree/classes/cpp/dbase/trunk/create_db.sql.in

CALL tango.init_tac_tables();

at line 56, and twice in
https://sourceforge.net/p/tango-cs/code/HEAD/tree/classes/cpp/dbase/trunk/stored_proc.sql.in

CALL tango.proc_release_nb(res_str);

and

SELECT exported,ior,version,pid,host
INTO tmp_exp,tmp_ior,tmp_version,tmp_pid,tmp_host
FROM tango.event

I'm not sure these are the only occurrences. Cheers,

Giovanni