Quosphere InfoSolutions
Celebal Interview Questions and Answers
Q1. What are views, functions, stored procedures
Views, functions, and stored procedures are database objects used to manipulate and retrieve data.
Views are virtual tables that display data from one or more tables in a specific way.
Functions are reusable code blocks that perform a specific task and return a value.
Stored procedures are precompiled SQL statements that can be executed with parameters.
All three objects can improve performance and simplify complex queries.
Examples include creating a view to display only certain ...read more
Q2. Write a query to get salary based on tenure of employees
Query to retrieve salary based on employee tenure
Use the DATEDIFF function to calculate the tenure of each employee
Join the employee and salary tables on the employee ID
Filter the results based on the tenure of the employee
Select the employee name and salary
Q3. Difference between where and having clause
WHERE clause filters rows before grouping and HAVING clause filters groups after grouping.
WHERE clause is used to filter rows based on a condition
HAVING clause is used to filter groups based on a condition
WHERE clause is used with SELECT, UPDATE, DELETE statements
HAVING clause is used with GROUP BY clause
WHERE clause is executed before GROUP BY clause
HAVING clause is executed after GROUP BY clause
Q4. Write a query to get manager commission based on employee commission
Query to calculate manager commission based on employee commission
Join the employee and manager tables on the manager ID
Calculate the total commission earned by each employee
Calculate the total commission earned by all employees under each manager
Calculate the manager commission as a percentage of the total employee commission
Return the manager name and commission amount
Q5. What are triggers
Triggers are database objects that automatically execute in response to certain events or changes in data.
Triggers can be used to enforce business rules and data integrity
They can be used to audit changes to data
Triggers can be used to replicate data to other systems
Examples of events that can trigger a trigger include INSERT, UPDATE, and DELETE statements
Q6. Delete duplicate rows
To delete duplicate rows, use the DISTINCT keyword or GROUP BY clause.
Use the DISTINCT keyword to select unique rows from a table.
Use the GROUP BY clause to group rows with the same values together.
Use the HAVING clause to filter out groups with more than one row.
Use the DELETE statement with a subquery to delete duplicate rows.
Example: DELETE FROM table_name WHERE id NOT IN (SELECT MIN(id) FROM table_name GROUP BY column_name);
Reviews
Interviews
Salaries
Users/Month
Made with ❤️ in India. Trademarks belong to their respective owners. All rights reserved © 2024 Info Edge (India) Ltd.
