The COLLATION_CHARACTER_SET_APPLICABILITY table indicates what character set is applicable for what collation.
The columns are equivalent to the first two display fields that we get from SHOW COLLATION.
mysql> desc INFORMATION_SCHEMA.COLLATION_CHARACTER_SET_APPLICABILITY;
+--------------------+-------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+--------------------+-------------+------+-----+---------+-------+
| COLLATION_NAME | varchar(64) | NO | | | |
| CHARACTER_SET_NAME | varchar(64) | NO | | | |
+--------------------+-------------+------+-----+---------+-------+
2 rows in set (0.00 sec)