IT Career Guides & Free Resources
Expert roadmaps, tutorials, salary guides and interview prep across Data Science, Generative AI, Python, Cloud & Analytics — written by GloryTecks trainers in Hyderabad.
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PySpark Interview Questions with Examples
PySpark interview questions test the API details that decide whether a job is correct and fast. Seven are answered on a real two-million-row electricity file that fights back: a placeholder that turns numbers into strings, dates without leading zeros that Spark 3 will not parse, and a UDF that drags rows into Python.
Redshift Interview Questions and Answers
Redshift interviews keep returning to two design choices: how rows are distributed across slices, and how they are sorted. Both are modelled here on three million real taxi trips, showing a distribution key that leaves five of eight slices idle, a join that moves 87.5% of rows, and a sort key that skips most blocks.
Mock Interview Guide: Practising Out Loud the Right Way
Reading answers is not the same as saying them under time pressure. This guide shows how to run mock interviews that improve performance: a realistic session format, a written scoring rubric, thinking aloud in technical rounds, recording and reviewing, and turning each session's weakest moment into the next practice.
Tableau Interview Questions and Answers
Tableau interviews return to one topic more than any other: when each calculation happens. This guide answers the core questions on FIXED, INCLUDE and table calculations, with the Tableau formulas and their results reproduced on a year of real online orders: one filter, two answers, 100% or 2.57%.
SQL Joins Interview Questions Explained
Join questions in interviews are rarely about syntax. They test whether you can predict how many rows come back. These nine questions, each answered with a query on three million real New York taxi trips, cover anti-joins, ON versus WHERE, NOT IN with NULLs, fan-out, self-joins, calendars and full outer joins.
Window Functions SQL Interview Questions
Interviewers use window functions to see whether you understand how SQL evaluates a query, not just the syntax. These nine questions, each answered with a query run on two years of real bike rentals, cover ranking ties, top N per group, running totals, the default frame trap, gaps and islands, and filtering.