10. 解决方案：CONCAT

CONCAT 解决方案

1. WITH t1 AS (
       SELECT LEFT(primary_poc,     STRPOS(primary_poc, ' ') -1 ) first_name,  RIGHT(primary_poc, LENGTH(primary_poc) - STRPOS(primary_poc, ' ')) last_name, name
       FROM accounts)
   SELECT first_name, last_name, CONCAT(first_name, '.', last_name, '@', name, '.com')
   FROM t1;

2.

WITH t1 AS (
    SELECT LEFT(primary_poc,     STRPOS(primary_poc, ' ') -1 ) first_name,  RIGHT(primary_poc, LENGTH(primary_poc) - STRPOS(primary_poc, ' ')) last_name, name
    FROM accounts)
SELECT first_name, last_name, CONCAT(first_name, '.', last_name, '@', REPLACE(name, ' ', ''), '.com')
FROM  t1;

3. WITH t1 AS (
       SELECT LEFT(primary_poc,     STRPOS(primary_poc, ' ') -1 ) first_name,  RIGHT(primary_poc, LENGTH(primary_poc) - STRPOS(primary_poc, ' ')) last_name, name
       FROM accounts)
   SELECT first_name, last_name, CONCAT(first_name, '.', last_name, '@', name, '.com'), LEFT(LOWER(first_name), 1) || RIGHT(LOWER(first_name), 1) || LEFT(LOWER(last_name), 1) || RIGHT(LOWER(last_name), 1) || LENGTH(first_name) || LENGTH(last_name) || REPLACE(UPPER(name), ' ', '')
   FROM t1;