gistfile1.txt

MariaDB [****]> explain select count(*) from api_person where age >= 50 and age <= 59;

+------+-------------+------------+-------+---------------------------------------------------------------------------------------------------------------------------------------+---------------------+---------+------+----------+--------------------------+
| id   | select_type | table      | type  | possible_keys                                                                                                                         | key                 | key_len | ref  | rows     | Extra                    |
+------+-------------+------------+-------+---------------------------------------------------------------------------------------------------------------------------------------+---------------------+---------+------+----------+--------------------------+
|    1 | SIMPLE      | api_person | range | person_age_internet,person_age_status_internet_income_worth,person_age_status_income_stage_master_internet,person3,person4,person_age | person_age_internet | 5       | NULL | 11879780 | Using where; Using index |
+------+-------------+------------+-------+---------------------------------------------------------------------------------------------------------------------------------------+---------------------+---------+------+----------+--------------------------+
1 row in set (0.81 sec)

MariaDB [****]> explain select count(*) from api_person where age >= 50 and age <= 59 and state = 'OR';
+------+-------------+------------+------+---------------------------------------------------------------------------------------------------------------------------------------+------+---------+------+----------+-------------+
| id   | select_type | table      | type | possible_keys                                                                                                                         | key  | key_len | ref  | rows     | Extra       |
+------+-------------+------------+------+---------------------------------------------------------------------------------------------------------------------------------------+------+---------+------+----------+-------------+
|    1 | SIMPLE      | api_person | ALL  | person_age_internet,person_age_status_internet_income_worth,person_age_status_income_stage_master_internet,person3,person4,person_age | NULL | NULL    | NULL | 27643940 | Using where |
+------+-------------+------------+------+---------------------------------------------------------------------------------------------------------------------------------------+------+---------+------+----------+-------------+
1 row in set (0.02 sec)

MariaDB [****]>