Channels a member is a part of

```sql
SELECT
c.displayName,
c.name
FROM
channels c
JOIN
channelmembers cm ON c.id = cm.channelid
JOIN
users u ON cm.userid = u.id
WHERE
u.username = 'professor';
```

The issue contains a SQL query for finding the channels joined by the user named professor, but it does not identify a target file or requested repository change. Review the repository's existing query organization first, then determine whether this query belongs there and what completion criteria apply.

Written by the indexing model from the issue text.