Author Topic: server  (Read 1563 times)

jackwill994

  • Yellow Belt
  • **
  • Posts: 30
  • Karma: +0/-0
server
« on: August 15, 2013, 07:45:23 AM »
What is the Linux Virtual Server?

mahesh1

  • Orange Belt
  • ***
  • Posts: 57
  • Karma: +0/-0
Re: server
« Reply #1 on: August 15, 2013, 07:48:59 AM »
Hello,

   The Linux Virtual Server is a highly scalable and highly available server built on a cluster of real servers, with the load

balancer running on the Linux operating system. The architecture of the server cluster is fully transparent to end users,

and the users interact as if it were a single high-performance virtual server.

Thanks,
Mahesh

sams

  • Orange Belt
  • ***
  • Posts: 78
  • Karma: +0/-0
Re: server
« Reply #2 on: September 01, 2013, 12:51:40 AM »
Hello sir,
What is the difference between trigger and rule?Can you help me please
Thanks

sumesh

  • Orange Belt
  • ***
  • Posts: 94
  • Karma: +0/-0
Re: server
« Reply #3 on: September 01, 2013, 01:10:03 AM »
Hello sir,
The triggers are called implicitly by database generated events, while stored procedures are called explicitly by client applications.
Thanks

rahesh.datasoft

  • Blue Belt
  • ****
  • Posts: 175
  • Karma: +0/-0
Re: server
« Reply #4 on: September 04, 2013, 04:53:00 PM »
Many things that can be done using triggers can also be implemented using the PostgreSQL rule system. One of the things that cannot be implemented by rules are some kinds of constraints, especially foreign keys. It is possible to place a qualified rule that rewrites a command to NOTHING if the value of a column does not appear in another table. But then the data is silently thrown away and that's not a good idea. If checks for valid values are required, and in the case of an invalid value an error message should be generated, it must be done by a trigger.

On the other hand, a trigger that is fired on INSERT on a view can do the same as a rule: put the data somewhere else and suppress the insert in the view. But it cannot do the same thing on UPDATE or DELETE, because there is no real data in the view relation that could be scanned, and thus the trigger would never get called. Only a rule will help.

siljy.datasoft

  • Green Belt
  • *****
  • Posts: 453
  • Karma: +0/-0
Re: server
« Reply #5 on: July 03, 2014, 04:30:57 AM »
hiiiiiiiii


The Linux Virtual Server is a highly scalable and highly available server built on a cluster of real servers, with the load balancer running on the Linux operating system. The architecture of the server cluster is fully transparent to end users, and the users interact as if it were a single high-performance virtual serve