Normalize emails under a declared policy · SQL
Task: the rules
Input contacts(id, email) — text. id is unique. Emails are ASCII and always present. Rules (this fictional system's declared policy) email: remove ASCII whitespace (space, tab, CR, LF) at both ends, then lowercase the whole address. Do not remove dots, plus tags or anything else; do not merge contacts. Running the rule twice changes nothing. Output (row order does not matter) clean(id text, email text)
Tab inserts spaces. Press Escape, then Tab, to move focus out of the editor.
| # | idstring | emailstring |
|---|---|---|
| 1 | c2e40 | ⇥s.am@Shop.Example.net· (raw value "\ts.am@Shop.Example.net ") |
| 2 | co4rf | ··carol_99@MAIL.example.org·· (raw value " carol_99@MAIL.example.org ") |
| 3 | cf5co | Sam+offers@example.COM |
| 4 | c3vyo | ··carol_99@Example.com·· (raw value " carol_99@Example.com ") |
| 5 | cgbcs | ⇥bob@example.com⇥ (raw value "\tbob@example.com\t") |
| 6 | cmnxs | ··Sam+offers@Shop.Example.net·· (raw value " Sam+offers@Shop.Example.net ") |
| 7 | crnsn | ·s.am@example.COM· (raw value " s.am@example.COM ") |
| 8 | c8m37 | ··sam+offers@mail.example.org·⇥ (raw value " sam+offers@mail.example.org \t") |
| 9 | c7og7 | ··s.am@MAIL.example.org·· (raw value " s.am@MAIL.example.org ") |
| 10 | cghwl | ·⇥carol_99@MAIL.example.org·⇥ (raw value " \tcarol_99@MAIL.example.org \t") |
| 11 | c80if | ·Ann.Lee@Example.com·· (raw value " Ann.Lee@Example.com ") |
| 12 | c942l | dan+news+2026@example.com |
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