Job sequences are created in just the same way as any other Datastage job, by dropping the icons for jobs onto the palette and linking them as appropriate.

Serial Job Sequence

Many jobs require one task to be complete before the next can start. In such a case, you'll simply want them chained together in the right order. Of course, you'll want to define what needs to happen if things go wrong and, for that purpose, you'll need to define exception handling, typically by linking an Exception component to an Email component…

                              
    ---------------       ---------------       ----------------       -----------------
   | DS40010GLOBAL |---->| DS40020SYNCDB |---->| DS40030DUMPREF |---->| DS40040LOADMAIN |
    ---------------       ---------------       ----------------       -----------------
                        
                          ---------------        ---------------
                         | DS40050EXCEPT |----->| DS40051MAILER |
                          ---------------        ---------------

The four jobs along the top are invoked one after the other. DS40050EXCEPT is an exception component to which Datastage will pass control, if it detects a problem. You add code to this component to identify the problem and generate the message you wish sent to your staff. DS40051MAILER is an email component, which will take the message and distribute it according to the distribution list you have defined.

Parallel Job Sequence

Wherever possible, you should run jobs in parallel. This makes the most use of your server resources, provided the total load on the machine doesn't lead to nasty side effects such as excessive swapping.

The standard way of handling parallel processing is to use a sequencer component to control the streams. Typically, condition components within each of the streams handle start up and wait processing for the stream. If the streams come together for unified processing, one or more additional sequencer components can be used to control this.

                         
                          --------------       ---------------
                       ->| D45011FREADY |---->| DS45010FRANCE |--
                      |   --------------       ---------------   |
                      |                                          |
  -----------------   |   --------------       ----------------  v    ------------------
 | D40005STARTREAD |---->| D45021GREADY |---->| DS45020GERMANY |---->| D45095STARTSPLIT |--> (etc)
  -----------------   |   --------------       ----------------  ^^    ------------------
                      |                                          ||
                      |   --------------       --------------    ||
                       ->| D45031IREADY |---->| DS45030ITALY |--- |
                      |   --------------       --------------     |
                      |                                           |
                      |   --------------       --------------     |
                       ->| D45041SREADY |---->| DS45040SPAIN |----
                          --------------       --------------