| Contains basic data for a Chunk |
| A Chunk is a unit for SDSS data export. It is a part of an SDSS stripe, a 2.5 degree wide cylindrical segment aligned at a great circle between the survey poles. A Chunk has had both strips completely observed. Since the SDSS camera has gaps between its 6 columns of CCDs, each stripe has to be scanned twice (these are the strips) resulting in 12 slightly overlapping narrow observation segments. Only those parts of a stripe are ready for export where the observation is complete, hence the declaration of a chunk, usually consisting of 2 runs. |
| name | type | length | unit | ucd | description |
| chunkID | bigint | 8 | ID_AREA | hash skyVersion, stripe, startMu, endMu | |
| skyVersion | tinyint | 1 | CODE_MISC | 0 = OPDB target, 1 = OPDB best | |
| targetVersion | varchar | 32 | ID_VERSION | version of target software | |
| startMu | int | 4 | arcsec | POS_LIMIT | Starting mu value |
| endMu | int | 4 | arcsec | POS_LIMIT | Ending mu value |
| stripe | int | 4 | ID_FIELD | Stripe number | |
| exportVersion | varchar | 32 | ID_VERSION | Export Version | |
| loadVersion | int | 4 | ID_VERSION | Load Version |