For Schemas:
SELECT default_character_set_name FROM information_schema.SCHEMATA
WHERE schema_name = "schemaname";
For Tables:
SELECT CCSA.character_set_name FROM information_schema.`TABLES` T,
information_schema.`COLLATION_CHARACTER_SET_APPLICABILITY` CCSA
WHERE CCSA.collation_name = T.table_collation
AND T.table_schema = "schemaname"
AND T.table_name = "tablename";
For Columns:
SELECT character_set_name FROM information_schema.`COLUMNS`
WHERE table_schema = "schemaname"
AND table_name = "tablename"
AND column_name = "columnname";
