OATI Senior Technical Lead Interview Questions and Answers

Containerization is a lightweight, portable, and self-sufficient way to package applications and their dependencies.

• Create a Dockerfile with instructions on how to build the container

• Build the Docker image using the Dockerfile

• Run the Docker image to create a container

• Deploy the container on a server using Docker Engine

Elastic Kubernetes Service (EKS) is a managed Kubernetes service provided by AWS.

• Fully managed Kubernetes service

• Automatically scales based on workload

• Integrates with other AWS services like EC2, S3, and IAM

CloudWatch is a monitoring and management service provided by AWS to monitor resources and applications in the cloud.

• CloudWatch collects and tracks metrics, logs, and events from various AWS services and resources.

• It provides real-time monitoring, alerting, and dashboards to help users visualize and understand their cloud environment.

• Users can set up alarms to notify them of changes in their environment or resource usa...read more

Java 11 introduced several new features and enhancements compared to Java 8.

• Local-Variable Syntax for Lambda Parameters

• HTTP Client API (standardized in java.net.http package)

• Nest-Based Access Control

• Dynamic Class-File Constants

• Epsilon: A No-Op Garbage Collector

• Flight Recorder

• ZGC: A Scalable Low-Latency Garbage Collector

call_form is used to call a form module from another form module, open_form is used to open a form module in a new window, and new_form is used to open a new form module in the same window.

• call_form is used to call a form module from another form module

• open_form is used to open a form module in a new window

• new_form is used to open a new form module in the same window

Forms personalization allows users to customize their own forms without modifying the underlying code, while customization involves making changes to the form's code.

• Forms personalization is done by end users without technical knowledge.

• Customization involves modifying the form's code by developers.

• Forms personalization is limited to changing the behavior of existing form elements.

• Customization allows for more extensiv...read more

Trigger firing sequence in Oracle Forms 12c involves pre-insert, pre-update, pre-delete, post-insert, post-update, and post-delete triggers.

• Pre-insert trigger fires before a new record is inserted.

• Pre-update trigger fires before an existing record is updated.

• Pre-delete trigger fires before a record is deleted.

• Post-insert trigger fires after a new record is inserted.

• Post-update trigger fires after an existing record is ...read more

Data skewness refers to the imbalance in the distribution of data values within a dataset.

• Data skewness occurs when certain values or categories appear more frequently than others in a dataset.

• It can lead to performance issues in data processing and analysis.

• To resolve data skewness, techniques like data partitioning, shuffling, and using appropriate algorithms can be employed.

• For example, in a dataset of customer tran...read more

The output of the query will depend on the specific data in the tables being joined.

• The result will be a combination of data from all 4 tables based on the join conditions specified in the query.

• Make sure to check for any filtering conditions in the query that may limit the output.

• The final result will include columns from all 4 tables, with rows that meet the join criteria.

Virtual DOM is a lightweight copy of the actual DOM in memory, used for efficient updates and rendering in web development.

• Virtual DOM is a concept used in frameworks like React to improve performance by minimizing actual DOM manipulations.

• When changes are made to the UI, the Virtual DOM is updated instead of the actual DOM.

• The Virtual DOM is then compared to the actual DOM, and only the differences are applied to the ...read more

Browser interprets JSX by transforming it into regular JavaScript using a transpiler like Babel.

• JSX is not directly understood by browsers, so it needs to be transpiled into regular JavaScript

• Babel is a popular transpiler used to convert JSX into JavaScript

• The transpiled JavaScript code is then executed by the browser

Design a batch process to create and send reports

• Create a script to generate the report based on specified criteria

• Schedule the script to run at regular intervals using a batch scheduler like cron

• Configure the script to send the report via email or save it to a shared location

• Include error handling and logging in the batch process

Spring Lifecycle is a series of steps that a Spring bean goes through from initialization to destruction.

• 1. Initialization phase: Bean is instantiated, dependencies are injected, and any initialization methods are called.

• 2. In use phase: Bean is used by the application.

• 3. Destruction phase: Bean is destroyed, any cleanup methods are called.

• 4. Post-processor phase: Additional processing can be done before or after initi...read more

DB structure refers to the organization of data in a database, including tables, relationships, and constraints.

• DB structure includes tables, columns, relationships, indexes, and constraints.

• Tables store data in rows and columns.

• Columns define the type of data that can be stored in a table.

• Relationships define how tables are connected to each other.

• Indexes improve the performance of database queries.

• Constraints enforce...read more

Code to get unique numbers from array of strings

• Convert array of strings to array of integers

• Use a Set to store unique numbers

• Convert Set back to array if needed