SQL Real-World Projects: Banking Database Tutorial

Customers Table

The Customers table holds personal data such as name, address, and contact information.

CustomerID is the primary key uniquely identifying each customer.

• CustomerID: INT, PRIMARY KEY
• Name: VARCHAR(100)
• Address: VARCHAR(255)
• Phone: VARCHAR(15)

Accounts Table

Accounts are linked to customers via CustomerID as a foreign key.

Each account has a type (e.g., savings, checking) and a balance.

• AccountID: INT, PRIMARY KEY
• CustomerID: INT, FOREIGN KEY
• AccountType: VARCHAR(50)
• Balance: DECIMAL(15,2)

Transactions Table

Transactions record all money movements related to accounts.

Each transaction has a type such as deposit, withdrawal, or transfer.

• TransactionID: INT, PRIMARY KEY
• AccountID: INT, FOREIGN KEY
• Amount: DECIMAL(15,2)
• Date: DATE
• Type: VARCHAR(20)

Implementing SQL Queries for Banking Operations

Once the schema is created, we can write SQL queries to perform banking operations.

These include inserting customers, creating accounts, and recording transactions.

• Insert new customers with INSERT statements.
• Open accounts linked to customers.
• Record deposits and withdrawals as transactions.
• Update account balances accordingly.

Ensuring Data Integrity and Security

Data integrity is crucial in banking to prevent errors and fraud.

Use constraints like PRIMARY KEY, FOREIGN KEY, and CHECK to enforce rules.

• Use transactions to ensure atomic operations.
• Implement constraints to prevent invalid data.
• Regularly back up the database.
• Limit access with user permissions.