Harmony Environmental Systems Interview Questions and Answers

To prepare an employee's attendance record, I would gather data on their attendance, create charts and graphs to visualize trends and patterns.

• Gather attendance data including dates, times, and reasons for absence or tardiness

• Create a spreadsheet or database to organize the data

• Use software like Excel or Tableau to create charts and graphs showing attendance trends

• Include metrics such as overall attendance rate, late arrivals, and absences

• Analyze the data to identify patterns...read more

DDL stands for Data Definition Language and is used to define the structure of database objects. DML stands for Data Manipulation Language and is used to manipulate data within the database.

• DDL is used to create, modify, and delete database objects such as tables, indexes, and views.

• DML is used to insert, update, delete, and retrieve data from database tables.

• Examples of DDL statements include CREATE TABLE, ALTER TABLE, and DROP TABLE.

• Examples of DML statements include INSERT...read more

SQL is divided into Data Definition Language (DDL), Data Manipulation Language (DML), Data Control Language (DCL), and Transaction Control Language (TCL).

• Data Definition Language (DDL) - used to define the structure of database objects like tables, indexes, and views. Examples include CREATE, ALTER, DROP.

• Data Manipulation Language (DML) - used to manipulate data stored in the database. Examples include SELECT, INSERT, UPDATE, DELETE.

• Data Control Language (DCL) - used to contr...read more

SQL is a standard language for managing databases, while MySQL is a specific open-source relational database management system.

• SQL is a standard language used to interact with databases, while MySQL is a specific database management system.

• SQL is an ANSI (American National Standards Institute) standard language, while MySQL is an open-source relational database management system.

• SQL can be used with various database management systems, while MySQL is specifically designed to ...read more

Joins are used to combine rows from two or more tables based on a related column between them.

• Joins are used in SQL to retrieve data from multiple tables based on a related column.

• Common types of joins include INNER JOIN, LEFT JOIN, RIGHT JOIN, and FULL JOIN.

• Example: INNER JOIN retrieves rows from both tables where the join condition is met.

• Example: LEFT JOIN retrieves all rows from the left table and the matched rows from the right table.

• Example: RIGHT JOIN retrieves all row...read more