notes on GEOTAIL CHANGES


The recipe output file name will not change.  It will be geotail_recon.output

Procedure Reconstruction1 will know that a quicklook session is being requested by seeing that the switch for the quicklook procedure DET_QL_WINDOW in set to 1.  Therefore, before calling Reconstruction1 for a Quicklook session, execute the following command:  exec switch.change ('DET_QL_WINDOW',1);  This will will tell reconstruction what kind of a session it needs to run.

Another usefull piece of information is that while reconstruction is running, you may not have to wait to find out the quicklook window of time.  functions QL.LL (quicklook, low limit of time) and QL.HL (quicklook, high limit of time) may be periodically querried for their values.  Both functions take as argument the name of the BFST.  e.g.:  exec dbms_output.put_line (ql.ll ('BFST342739471347312BAD'));

should any of the above fuctions return -1 this means that the windown of time has not yet been determined.  Should any of these functions return 0 this means that no window of time as small as the paramterer (QL_SPAN_DEC_RATE, quicklook span rate or decrease) could be found.  Else the function will allways returns two values.  

The reconstruction output file will contain dynamic messages that will indicate what the Quicklook window of time is, if any.  One may also know a window of time is now available by looking out for the rule number that would have computed it, in the Monitor_system_state virtual instrument (the rule is DET_QL_WINDOW).
Note that both values returned by the latter two functions are stored in the sessions_parameters table once they have been determined (columns QL_LOW_LIM and QL_HIGH_LIM), therefore one may also periodically querry this table if one so chooses.

There are now three input parameters to procecedure RECONSTRUCTION1.  Beside the name of the GFST and that of the BFST, RECONSTRUCTION1 now takes a third optional parameter that is the floating point datetime constraint to use during a quicklook session.  Note again that this parameter is optional, i.e. that during a normal reconstruction, it need not be included in the parameter list (Oracle will ignore it if it is included);  however during a quicklook session, Oracle will expect the third argument to the procedure RECONSTRUCTION1 to be valid.


Note because the gfst is modified during a quicklook session, it is dropped at the end of the session; therefore if a normal reconstruction is to follow the quicklook session, procedure DET_QL_WINDOW must be turned off as shown earlier and only the GFST need to be re-posted into the database.