gistfile1.txt

MariaDB []> explain select count(*) from api_person where age in (50,51)  and state = 'OR';
+------+-------------+------------+-------+---------------------------------------------------------------------------------------------------------------------------------------+---------------------+---------+------+--------+------------------------------------+
| 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 | 955522 | Using index condition; Using where |
+------+-------------+------------+-------+---------------------------------------------------------------------------------------------------------------------------------------+---------------------+---------+------+--------+------------------------------------+
1 row in set (0.00 sec)

MariaDB []> explain select count(*) from api_person where age in (50,51,52,53,54,55,56,57,58,59)  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 | 27609895 | Using where |
+------+-------------+------------+------+---------------------------------------------------------------------------------------------------------------------------------------+------+---------+------+----------+-------------+
1 row in set (0.00 sec)