Database size
MIPL will receive two types of data for the DS1 mission: image and
navigation. Each image and navigation file contains a set of blocks.
A record is inserted or updated in the ds1 database for each packet
in a file.
Over the life of the mission, MIPL expects to receive a total of
approximately 1,500 image files and 4 to 8 navigation files.
(The actual number of navigation files will be much larger than
number, but old versions of navigation files are replaced with
new ones as they arrive, so the total number of navigation files
on hand at any one time is 4 to 8.)
Each file contains about 2,000 blocks, so each file results in 2,000
entries in the database. Image files are unique, so we expect to
store 1,500 x 2,000 => 3,000,000 records describing image blocks.
The set of navigation files get updated, so current rows in the
database that describe navigation blocks get updated as well. For
8 navigation files, each with 2,000 blocks, the database will store
16,000 rows in the database. (When a navigation file is first received,
packet data is inserted. After that, rows are updated as replacement
navigation files arrive.
The total number of rows for both types of files is approximately
3,016,000. Note the navigation files will cause a large number of
updates to occur. This is the most expensive type of database
operation in terms of transaction log storage requirements, so the
database's transaction log must be sized accordingly.
Data rates
On a weekly basis, MIPL can expect to receive bursts of 4 images
files or 1 navigation file. At most, this should result in
4 x 2,000 => 8,000 new records per week.
The 'ds1' database contains two primary user tables, 'ds1Files' and 'blocks'.
Estimated sizes of each table were computed using 'sp_estspace':
sp_estspace ds1Files, 1500, NULL, "name" => 0.27 MBs
sp_estspace blocks, 3000000 => 64.53 MBs
The space require for the definition of objects in the database is ~ 5.5 MBs.
The recommented starting size of the database is 75 MBs.
