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6 rows affected
| PREV_USERID | USERID | |
|---|---|---|
| null | abc | common@email.com |
| abc | xyz | common@email.com |
| xyz | pqr | common@email.com |
| null | x05 | peter@email.com |
| x05 | a17 | peter@email.com |
| a17 | a01 | peter@email.com |