Data Structure
Networking
RDBMS
Operating System
Java
MS Excel
iOS
HTML
CSS
Android
Python
C Programming
C++
C#
MongoDB
MySQL
Javascript
PHP
Physics
Chemistry
Biology
Mathematics
English
Economics
Psychology
Social Studies
Fashion Studies
Legal Studies
- Selected Reading
- UPSC IAS Exams Notes
- Developer's Best Practices
- Questions and Answers
- Effective Resume Writing
- HR Interview Questions
- Computer Glossary
- Who is Who
Displaying Department Name Having Most Number of Employees in SQL Server
Introduction
Displaying the department with the most number of employees in SQL Server is a common task that can be accomplished using a SQL query. The query will typically involve joining the employees and departments tables on the department ID, grouping the results by department name, and counting the number of employees in each department. Then use aggregate functions like COUNT() and TOP 1 with ORDER BY clause to get the desired result.
To display the department name that has the most number of employees in SQL Server, it requires to have two database tables - Employees and Departments with some relationships. Employees table will contain the employee details such as EmployeeID, EmployeeName, DepartmentID, etc., and the Departments table will contain the Department details such as DepartmentID, DepartmentName, etc. DepartmentID in both tables will be used as a relationship.
Definition
To display the department name that has the most number of employees in SQL Server, you can use a query that joins the employees and departments tables on the department ID, and then group the results by department name and count the number of employees in each department. Finally, you can use the ORDER BY clause to sort the results in descending order of the number of employees and the TOP clause to limit the results to just the department with the highest number of employees.
Steps
Create a Database
To create a database in SQL Server, you can use the CREATE DATABASE statement.
CREATE DATABASE EmployeeDB;
This will create a new database called EmployeeDB.
Create a table
To create a table for storing employee information, you can use the CREATE TABLE statement.
USE EmployeeDB; CREATE TABLE Employee ( EmployeeID INT PRIMARY KEY, FirstName NVARCHAR(50), LastName NVARCHAR(50), Department NVARCHAR(50) );
This will create a table called Employee with four columns: EmployeeID, FirstName, LastName, and Department. The EmployeeID column is set as the primary key, which ensures that each employee has a unique ID.
Display the Department Name
To display the department name that has the most number of employees, you can use a query like the following −
USE EmployeeDB; WITH DepartmentCounts AS ( SELECT Department, COUNT(*) AS EmployeeCount FROM Employee GROUP BY Department ) SELECT Department FROM DepartmentCounts WHERE EmployeeCount = (SELECT MAX(EmployeeCount) FROM DepartmentCounts);
This query uses a common table expression (CTE) called DepartmentCounts to count the number of employees in each department. The CTE is then used to select the department with the maximum number of employees.
To Insert data
You would need to first insert data into the created table 'Employee' using INSERT INTO statement
INSERT INTO Employee (EmployeeID, FirstName, LastName, Department) VALUES (1, 'John', 'Doe', 'IT'), (2, 'Jane', 'Doe', 'HR'), (3, 'Bob', 'Smith', 'IT'), (4, 'Samantha', 'Johnson', 'HR'), (5, 'Mike', 'Williams', 'IT'), (6, 'Emily', 'Jones', 'HR');
Then you can use the above select query to fetch the department which have most number of employees.
To fetch
To fetch the department which have most number of employees, you can use a query like the following −
WITH DepartmentCounts AS ( SELECT Department, COUNT(*) AS EmployeeCount FROM Employee GROUP BY Department ) SELECT TOP 1 Department FROM DepartmentCounts ORDER BY EmployeeCount DESC;
This query uses a common table expression (CTE) called DepartmentCounts to count the number of employees in each department and it is grouped by department, so the COUNT(*) function will give the count of employees in each department.
The outer query then selects the top 1 department where the count of employees is in descending order. In this way, it will return the department name having most number of employees.
You can use SELECT TOP N if you want to retrieve more than one department name.
Please make sure you are in the right context of database, and table 'Employee' exist before running this query. Also, make sure you have enough data in the table Employee, otherwise, this query will return empty results.
Conclusion
To display the department name that has the most number of employees in SQL Server, you can use a query that uses a common table expression (CTE) to count the number of employees in each department, and then select the department with the maximum number of employees.
It's important to make sure that you are in the right context of the database and that the 'Employee' table exists before running any of the queries, also make sure you have enough data in table Employee to make sure the results will be meaningful.
2K+ Views
