Explain Different Types of SQL Queries | Dataford Interview Questions

Explain different type of SQL query?

Asked in the Technical round stage. Round 1 - Technical. Using the provided customer, account, and transaction tables, write a query that demonstrates a practical reporting query. Include January 2024 transactions only, classify each qualifying customer by net flow, and exclude customers with no positive January credits.

Output

One row per qualifying customer with customer_id, customer_name, account_count, total_credits, total_debits, net_flow, and financial_position
Sort by net_flow descending, then customer_id ascending
Include customers with positive January credits, including customers whose net flow is negative

Schema

customers

Column	Type	Description
customer_idPK	INT	Unique customer identifier
customer_name	VARCHAR(100)	Customer's full name

accounts

Column	Type	Description
account_idPK	INT	Unique account identifier
customer_id	INT	Customer who owns the account
account_type	VARCHAR(30)	Type of account

transactions

Column	Type	Description
transaction_idPK	INT	Unique transaction identifier
account_id	INT	Account associated with the transaction
transaction_type	VARCHAR(20)	Credit or debit transaction
amount	DECIMAL(12,2)	Transaction amount
transaction_date	DATE	Date the transaction occurred

Your question is Explain Different Types of SQL Queries. Start with the requirements and the three tables in the Question tab.

Run and submit as often as you like. When you're ready, talk me through your approach or go straight to the code.

Problem