func_odbc.conf:
	[PRUEBA_MYSQL]
	dsn=asterisk
	readsql=SELECT '234'

res_odbc.conf:
	[asterisk]
	enabled => yes
	dsn => asterisk-connector
	username => *********
	password => *********
	pooling => no
	limit => 5
	pre-connect => yes

odbc.ini:
	[asterisk-connector]
	Descripcion     = Mysql connection to 'asterisk' database
	Driver          = MySQL
	Database        = asterisk
	Server          = localhost
	Username        = *******
	Password        = *******
	Port            = 3306
	Socket          = /var/run/mysqld/mysqld.sock
	TraceFile  = /tmp/odbc.trace
	Trace      = 1

extensions.conf:
	exten => mysql,1,Set(RES1=${ODBC_PRUEBA_MYSQL})
	exten => mysql,2,NoOp(MySql-->${RES1}<--)
	exten => mysql,3,Hangup()

CLI show:
 -- Executing [mysql@from-internal-sistema:1] Set("SIP/26-00000009", "RES1=")
 -- Executing [mysql@from-internal-sistema:2] NoOp("SIP/26-00000009", "MySql--><--")
 -- Executing [mysql@from-internal-sistema:3] Hangup("SIP/26-00000009", "")