I have below table KEY_STATUS.
|| KEY || STATUS || | 0001 | FAILED | | 0001 | COMPLETED | | 0002 | FAILED | | 0003 | COMPLETED | | 0002 | FAILED | | 0004 | STARTED |
I would like to select keys with only FAILED state. That means I will have to exclude 0001 as it has both FAILED and COMPLETED, also exclude 0003 as it has COMPLETED state. Output should be
|| KEY || STATUS || | 0002 | FAILED |
What approach should I take in Oracle to achieve above?