user (멘티)

- id
- name
- email
- password
- role
- profile_image
- interest (관심분야)
- provider (로컬, 소셜로그인)
- introduction
- created_at
- updated_at
- is_deleted

mentors (멘토확장)

- id
- user_id
- company
- experience
- hourly_rate (시간당 가격)
- 경력 증명서, 포트폴리오, github 

tech_stacks (기술 스택)

- id
- stack

mentor_tech_stacks (멘토-기술스택)

- id
- mentor_id
- tech_stack_id

sessions (세션)

- id
- mentor_id
- title
- description
- method (온라인, 오프라인)
- type (그룹, 개인)
- max_participants
- duration (몇분하는지..)
- price
- created_at
- updated_at
- is_closed

available_days (가능한 요일)

- id
- day
- time

session_available_days (세션-가능한 요일)

- id
- session_id
- available_day_id