chore: adds useful SQL scripts for devops (#14068)

scripts/find-email-case-insensitive-duplicates.sql

@@ -0,0 +1,13 @@
+-- Find users with uppercase characters in email
+SELECT * FROM users u WHERE u.email ~ '[[:upper:]]';
+
+-- Find emails with case insensitive duplicates
+SELECT lower(email) FROM users GROUP BY lower(email) HAVING count(*) > 1;
+
+-- List emails with their case insensitive duplicates
+SELECT * FROM users u WHERE LOWER(u.email) IN (
+  SELECT lower(email) FROM users GROUP BY lower(email) HAVING count(*) > 1
+);
+
+-- Lowercase all user emails (This will fail if there are case insensitive duplicates)
+UPDATE users SET email = lower(email) WHERE email ~ '[[:upper:]]';