ID Checking balance Accounts startedDate Saving ID CATE TABLE OPERATIONS( CHAR(10), Dunt DECIMAL(9,2), praction Date DATE interest budget name addres Branches Opens Operations amount state phone transactDate name ID email phones Customers dob wert the above ER diagram to relations in the Cross Reference approach for the relationship set Operations. The following SQL statement is intended to de referential integrity constraints.
ID Checking balance Accounts startedDate Saving ID CATE TABLE OPERATIONS( CHAR(10), Dunt DECIMAL(9,2), praction Date DATE interest budget name addres Branches Opens Operations amount state phone transactDate name ID email phones Customers dob wert the above ER diagram to relations in the Cross Reference approach for the relationship set Operations. The following SQL statement is intended to de referential integrity constraints.
Related questions
Question
Transcribed Image Text:### Understanding the ER Diagram
The image presents an Entity-Relationship (ER) diagram illustrating the relationships between `Branches`, `Accounts`, `Customers`, `Operations`, `Checking`, and `Saving`.
#### Entities and Attributes:
1. **Branches**:
- Attributes: `ID`, `street`, `city`, `state`, `budget`, `address`, `phone`
2. **Customers**:
- Attributes: `ID`, `name`, `email`, `phone`, `dob`, `ssn`
3. **Accounts**:
- Attributes: `ID`, `balance`, `startedDate`
4. **Account Types**:
- **Checking**:
- Attribute: `fee`
- **Saving**:
- Attribute: `interest`
#### Relationships:
1. **Opens**:
- Connects `Branches` and `Accounts`
- Attributes: `amount`, `transactDate`
- The relationship is many-to-many (N:M)
2. **Operations**:
- Connects `Accounts` and `Customers`
- Attributes: `amount`, `transactDate`
- The relationship is many-to-many (M:N)
### Converting ER Diagram to SQL Table
The text below the diagram explains converting the ER diagram into relational tables using a cross-reference approach for the relationship set `Operations`. The provided SQL statement intends to define the `OPERATIONS` table but requires corrections.
#### Initial SQL Statement for `OPERATIONS` Table:
```sql
CREATE TABLE OPERATIONS(
ID CHAR(10),
Amount DECIMAL(9,2),
TransactionDate DATE,
PRIMARY KEY(ID),
FOREIGN KEY(ID) REFERENCES Customers(ID),
FOREIGN KEY(ID) REFERENCES Accounts(ID)
);
```
### Tasks:
1. **Explain why the SQL statement does not work correctly:**
- The table `OPERATIONS` incorrectly assigns the same attribute `ID` for both `Customers` and `Accounts`. This leads to ambiguity and violates referential integrity constraints because a single `ID` cannot reference two different foreign keys simultaneously.
2. **Corrected SQL Statement:**
- To correct the statement, separate distinct foreign keys for `Customers` and `Accounts` should be added. Here is the corrected version:
```sql
CREATE TABLE OPERATIONS(
OperationID CHAR(10),
Amount DECIMAL(9,2),
TransactionDate DATE,
Customer
Expert Solution
This question has been solved!
Explore an expertly crafted, step-by-step solution for a thorough understanding of key concepts.
Step by step
Solved in 4 steps
