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TOPICS
Build idempotent double opt-in signup
1
·
Flaviocopes
·
Aug. 3, 2026, 6:18 p.m.
SQL
Double Opt-in
Email Confirmation
Subscriber Management
Summary
Use a conditional SQL upsert to prevent duplicate subscribers, limit confirmation resends, and recover immediately after failed email delivery....
Read full post on flaviocopes.com →
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