SQL for Analytics

Overview
Technical Aspect
Customer Orders
Employee Incentive
Research Papers
Author

Overview

The usage of SQL Programming language is used to fetch data from Database is demonstrated. There are three problem statements related to Customer orders, Employee incentives and research papers of an university.

Technical Aspect

The project is devided into three parts:

creating tables and inserting data into Database
Understanding attributes, relationship between entities with the help of ER diagrams
Fetch data as per requirement for Analytical insights, the following sql syntax/functions used:
- Aggregate Functions
- Filters
- Clauses
- Sub Queries(nested,correlated)
- Joins
- Window Functions

Q1 Problem statement

Find all the non-local orders by looking at the salesmen that generated orders for their customers but are located elsewhere unlike their customers, and fetch the details like order_no, name of the customer, customer_id, salesman_id.

Input data of Q1

Query for Q1


SELECT 
	o.order_no, c.name, o.customer_id, s.id 		-- required fields from tables
FROM 
	salesman s 						-- Inner Join & alliasing
	INNER JOIN customer c
	  ON c.salesman_id = s.id
	INNER JOIN orders o
 	  ON o.customer_id = c.id 				-- Appropriate relations on common fields
WHERE 
	s.city != c.city 					-- for non local orders
ORDER BY 
	order_no 						-- sorting the orders

output data of Q1

Q2 Problem statement

A food store is planning to give incentive to it's employees based on their monthly performance in sales.Incentive is different for each position and each position have it's max limit for incentive. Sales target to avail the incentive is a milestone. Employee makes incentive everytime he completes a milestone of sales. Milestone is different for each position. You are given the data for a month in the database store_data. Task: Find amount of incentive made by each employee.

Input data of Q2

Query for Q2

SELECT 
	e.employee_id,
CASE 
	WHEN ((ROUND(e.emp_sale/i.sales_milestone))*i.incentive) < i.cap
	THEN ((ROUND(e.emp_sale/i.sales_milestone))*i.incentive)
	WHEN ((ROUND(e.emp_sale/i.sales_milestone))*i.incentive) > i.cap
	THEN i.cap
END incentive_made 						-- use of CASE clause to categorise the incentive made 
FROM 
	employee e INNER JOIN incentive_details i
	  ON e.pos_id = i.p_id
ORDER BY 
	e.employee_id						-- sorting the orders

output data of Q2

Q3 Problem statement

There are research institutes with Researchers who have written papers under the guidance of their mentors. You are given a database named ResearchInstitute for one such Institution. Task: Write an SQL Query to find subjects that contain the alphabet "b" and have papers written under the guidance of more fenale mentors.

Input data of Q3

Query for Q3

SELECT 
	p_subject
FROM
 	(SELECT *, MAX(ct) OVER (PARTITION BY m_gender,P_subject) mc
 	FROM
 		(SELECT 
 			m_gender, p_subject, COUNT(*) AS ct
		 FROM
 			mentors me INNER JOIN research_mentor rm 	-- Inner join of tables
 			  ON me.m_id = rm.m_id
 			INNER JOIN researchers r 
 			  ON r.r_id = rm.r_id
 			INNER JOIN research_paper rp
 			  ON rp.r_id = r.r_id
 			INNER JOIN papers p
 			  ON p.p_id = rp.p_id
 		WHERE 
 			p_subject LIKE '%b%' 				-- subject with b letter 
 		GROUP BY m_gender, p_subject) a
 		) b
 WHERE 
 	m_gender = 'F' 							-- filtering gender
 AND
 	ct = mc 							-- filtering the max paper written under female mentor

varma-prasad / SQL-for-Analytics

SQL for Analytics

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