Timeline for Joining 4 tables and selecting distinct values based on 3 timestamps
Current License: CC BY-SA 3.0
4 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Mar 13, 2015 at 5:56 | comment | added | breaking_brain | would you mind briefly explaining what the row_number() section does? the query seems to work alright! | |
| Mar 13, 2015 at 2:32 | comment | added | breaking_brain | dv.results, dw.results, tt.results identifies the testing. dv.date_test, dw.date_test, tt.date_test are the columns used for ordering. so i think the intent is to get distinct data from dw.results by selecting only data that is latest in dw.date_test and join it with dv.results selecting latest by dv_date.test and join it with tt.results selecting latest by tt.date_test. | |
| Mar 13, 2015 at 2:24 | comment | added | breaking_brain | so each part undergoes 3 different tests(dv,dw,tt) and the date_test record the date of the test being done. but if the part fails any of the test, it would need to undergo a re-test. when i query it using my query, i would have duplicates of the part_id as it has undergone a re-test. | |
| Mar 12, 2015 at 10:01 | history | answered | ypercubeᵀᴹ | CC BY-SA 3.0 |