Хотя вы не указали это, я подозреваю, что вам нужны итоги за различные периоды времени:
SELECT
SUM(date_added > NOW() - INTERVAL 5 SECOND) as total_in_last_5_seconds,
SUM(date_added > NOW() - INTERVAL 5 MINUTE) as total_in_last_5_minutes,
SUM(date_added > NOW() - INTERVAL 5 HOUR) as total_in_last_5_hours,
SUM(date_added > NOW() - INTERVAL 5 DAY) as total_in_last_5_days,
SUM(date_added > NOW() - INTERVAL 5 WEEK) as total_in_last_5_weeks,
SUM(date_added > NOW() - INTERVAL 5 MONTH) as total_in_last_5_months,
SUM(date_added > NOW() - INTERVAL 5 YEAR) as total_in_last_5_years
from records;
Отредактировано: добавлена альтернатива, предложенная комментарием
Если вы хотите фактические записи, это будет классифицировать их:
SELECT
*,
case
when date_added > NOW() - INTERVAL 5 SECOND then 'last_5_seconds'
when date_added > NOW() - INTERVAL 5 MINUTE then 'last_5_minutes'
when date_added > NOW() - INTERVAL 5 HOUR then 'last_5_hours'
when date_added > NOW() - INTERVAL 5 DAY then 'last_5_days'
when date_added > NOW() - INTERVAL 5 WEEK then 'last_5_weeks'
when date_added > NOW() - INTERVAL 5 MONTH then 'last_5_months'
when date_added > NOW() - INTERVAL 5 YEAR then 'last_5_years'
else 'ancient'
end as time_category
from records;