mysql - Selecting a COUNT of values, grouped by that same column, distinct on another -


here's sample schema:

| type_id | university_id | --------------------------- |    1    |      u01      | |    2    |      u01      | |    2    |      u01      | |    3    |      u02      | |    4    |      u02      |

and want count of amount of records have same university_id, university_id itself, , must not include duplicates of type_id, result same data given above:

| university_id | count(university_id) | ---------------------------------------- |      u01      |          2           | |      u02      |          2           |

right i'm trying following, give me count(u01) of 3 instead of 2

select university_id, count(university_id) table group university_id

is possible want, , if how?

you should count type_id uniquely not university_id

select university_id, count(distinct type_id) totalcount   tablename group  university_id

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