Keywords: MiddleWG
Hi Robyn,
I'll let Ray address the first part.
Regarding the second part:
Yes, the CCD's map to a region of the sky so this is another 'natural' chunking
for an ingest file. However, this doesn't imply that the sources or objects
in the ingest file which are derived from the CCD's projection on the sky
will match any sort of segmenting being done on the source/object DB tables.
Which raises a question for the post-DC1 object DB: will it be segmented
based on regions (tiled pattern on sky) or zones (swathes in the sky)?
Will it be monolithic?
Our current model is that:
- at the base: object DB will be segmented, we will maintain
one table for each stream of data and will continue adding
data to it. We will not move/recluster/repartition data
(there is no time if we want to meet 30-40 sec requirement)
- at the main archive: object DB will be repartitioned: we will
"merge" data from the intermediate (temporary) tables used for
ingest into smaller number of larger tables. How we cluster
data in the final (merged) tables is not well understood yet,
I guess we will start with clustering data spatially.
thanks,
Jacek
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