IQVIA Software Engineer Level 1 Interview Questions and Answers

SQL is necessary for most projects involving databases to manage and query data efficiently.

• SQL is essential for creating, updating, and querying databases in most projects.

• Without SQL, it would be challenging to interact with databases and retrieve specific data.

• Examples of SQL commands include SELECT, INSERT, UPDATE, and DELETE.

• SQL can help optimize database performance and ensure data integrity.

HQL stands for Hibernate Query Language, a query language similar to SQL but used for Hibernate ORM framework.

• HQL is used to perform database operations in Hibernate ORM framework.

• It is similar to SQL but operates on Hibernate objects instead of database tables.

• HQL queries are written in Hibernate-specific syntax.

• Example: 'FROM Employee e WHERE e.department = :dept'

• HQL queries are translated into SQL queries by Hiberna

Views in Java are user interface components that display data from a model in a specific format.

• Views are used to represent the user interface in Java applications.

• They display data from a model in a visually appealing format.

• Examples include buttons, text fields, labels, and checkboxes.

Cross joins are a type of join operation in SQL that combines each row from one table with each row from another table.

• Cross joins do not have a join condition specified, resulting in a Cartesian product of the two tables.

• They can be used when you want to combine every row from one table with every row from another table.

• Cross joins can lead to a large result set if the tables being joined have many rows.

Delete removes rows one by one, while truncate removes all rows at once.

• Delete is a DML command, while truncate is a DDL command.

• Delete can be rolled back, while truncate cannot be rolled back.

• Delete fires triggers, while truncate does not fire triggers.

• Delete is slower as it logs individual row deletions, while truncate is faster as it logs the deallocation of the data pages.