ER Diagram - U.S. House of Representatives Votes

ER Diagram: U.S. House of Representatives Votes

Database Management, Spring 2026 — Assignment #3

Entity Details（實體詳細資訊）

Entity	Attributes	PK	Description
STATE	StateName, Region	StateName	U.S. State. Region ∈ {Northeast, Midwest, Southeast, Southwest, West}（美國州，含地區分類）
CONGRESS_PERSON	CpId, Name, StartDate, Party	CpId	House Representative. Party ∈ {Republican, Democrat, Independent, Other}（眾議員，含政黨）
BILL	BillName, DateOfVote, Passed	BillName	Proposed law. Passed ∈ {Yes, No}（法案，含投票日期和通過與否）

Entity

Attributes

Description

STATE

StateName, Region

StateName

U.S. State. Region ∈ {Northeast, Midwest, Southeast, Southwest, West}（美國州，含地區分類）

CONGRESS_PERSON

CpId, Name, StartDate, Party

CpId

House Representative. Party ∈ {Republican, Democrat, Independent, Other}（眾議員，含政黨）

BILL

BillName, DateOfVote, Passed

BillName

Proposed law. Passed ∈ {Yes, No}（法案，含投票日期和通過與否）

Relationship Details（關係詳細資訊）

Relationship	Entities	Cardinality	Attributes	Description
Represents	STATE — CONGRESS_PERSON	STATE(1,N) — CP(1,1)	—	A congressperson represents exactly one state; a state has at least one representative.（一個議員代表一個州；一個州至少有一個議員。）
Sponsors	CONGRESS_PERSON — BILL	CP(0,N) — BILL(1,N)	—	A bill has at least one sponsor; a congressperson can sponsor many bills (or none).（一個法案至少有一個提案人；一個議員可以提案多個法案。）
Votes_On	CONGRESS_PERSON — BILL	CP(0,N) — BILL(0,N)	Vote {Yes, No, Abstain, Absent}	Tracks how each congressperson voted on each bill.（追蹤每個議員對每個法案的投票。）

Relationship

Entities

Cardinality

Attributes

Description

Represents

STATE — CONGRESS_PERSON

STATE(1,N) — CP(1,1)

—

A congressperson represents exactly one state; a state has at least one representative.（一個議員代表一個州；一個州至少有一個議員。）

Sponsors

CONGRESS_PERSON — BILL

CP(0,N) — BILL(1,N)

—

A bill has at least one sponsor; a congressperson can sponsor many bills (or none).（一個法案至少有一個提案人；一個議員可以提案多個法案。）

Votes_On

CONGRESS_PERSON — BILL

CP(0,N) — BILL(0,N)

Vote {Yes, No, Abstain, Absent}

Tracks how each congressperson voted on each bill.（追蹤每個議員對每個法案的投票。）

Assumptions（假設）:

CpId is introduced as a surrogate primary key for CONGRESS_PERSON, since Name alone may not be unique.（引入 CpId 作為議員的代理主鍵，因為姓名可能不唯一。）
BillName is assumed to be unique within the current two-year session and serves as PK for BILL.（假設法案名稱在當前兩年會期內唯一。）
Each congressperson represents exactly one state (district is within a state).（每個議員只代表一個州。）
A bill must have at least one sponsor (congressperson who proposed it).（每個法案至少有一個提案人。）
Not every congressperson votes on every bill (may be Absent), hence (0,N) on both sides of Votes_On.（不是每個議員都會對每個法案投票，可能缺席。）
The database tracks only the current two-year congressional session.（資料庫只追蹤當前兩年會期。）

Assignment #3 — Database Management, Spring 2026 — 1134542 俞綱皓