How to create a SQL statement that only return the result if one of the row contain the desired value?

Question

My goal is to return the admins list only if the requester's username is registered as admin / member in that channel.

I store the admins and members list in TABLE channel_member.

CREATE TABLE channel_member (
    id INTEGER NOT NULL,
    uuid VARCHAR(255) NOT NULL,
    user VARCHAR(255) NOT NULL,
    role VARCHAR(255) NOT NULL, // '0' = admin, '1' = member
    PRIMARY KEY (id)
);

What I've tried:

1. This SELECT statement return multiple row regardless whether the username exists as admin or member.

  @Select("SELECT user_detail.user, user_detail.name " +
          "FROM user_detail " +
          "JOIN channel_member ON user_detail.user=channel_member.user " +
          "AND channel_member.uuid=#{channelUuid} AND channel_member.role='0'")
  List<MemberModel> getChannelAdmins(String username, String channelUuid);

What I am thinking what the logic would look like but don't know how to write it into a SELECT statement:

1. Get the TABLE user_detail
2. Get the TABLE channel_member
3. JOIN table user_detail and channel_member / get intersection that:
   1. channel_member.uuid=#{channelUuid}
   2. channel_member_role='0' // for admin.
4. (I don't know how) return the result only if channel_member.user=#{username} found in one of the row.

TL:DR, I will post the data down below and the expected result

Table user_detail

id | user       | name
1  | admin      | admin client
2  | member     | member client
3  | member-2   | member 2 client
4  | non-member | non member client

Table channel_member

id | uuid | user     | role
1  | 1    | admin    | 0
2  | 1    | member   | 1
3  | 1    | member-2 | 1
4  | 2    | admin    | 0

The query is (username, channelUuid) e.g (member-2, 1) to get the Admins list.

My expected result is

[
  {
    user: "admin",
    name: "admin client",
  },
]

Another query is (non-member, 1)

My expected result is

[]