#1074 rest: set_mode: add support for different ogserver addresses

Add foreign key "identornos" from table "entornos" to table
"ordenadores".

A row in table "entornos" represent a valid ogServer address.
Multiple ogServer valid addresses can exist when running several
instances or a single ogServer instance is exposed to different networks.

Can't delete rows in "entornos" table nor update their id (primary
key) if the row has any associated clients ({ON UPDATE/ON DELETE} RESTRICT).

Allows assigning different but valid ogServer IPs to clients.
Enabling support for multiple instances of ogServer (e.g: load balancing) or
exposing a single ogServer instance to different networks (e.g: VLAN).

Look up for the valid ogServer IP of a given client when changing a
client's mode (og_set_client_mode).

Determines valid ogServer IP using a JOIN statement.

	JOIN entornos USING(identorno)

Reuses the fetched ip using a statement variable.

	@serverip:=entornos.ipserveradm

For example, for a two VLAN setup:

	vlan1 ogserver: 192.168.56.10
	vlan2 ogserver: 192.168.57.10

The "entornos" table should look like:

	identorno       ipserveradm             ...
	---------       -----------             ...
	1               192.168.56.10           ...
	2               192.168.57.10           ...

And computers in the "ordenadores" table might look like:

	idordenador     identorno       ...
	----------      ---------       ...
	1               1               ...
	2               1               ...
	3               2               ...
	4               2               ...
	...             ...             ...

Additionally, splits the SQL query for better readability.

Co-authored-by: Jose Guisado <jguisado@soleta.eu>

0 files changed, 0 insertions, 0 deletions