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Keyword is AI– This is your go-to space to ask questions, share programming tips, and engage with fellow coding enthusiasts. Whether you’re a beginner or an expert, our community is here to support your journey in coding. Dive into discussions on various programming languages, solve challenges, and exchange knowledge to enhance your skills.

  • All major PySpark data structures and types Discussed

    🔍 What Does collect_list() Do in Spark SQL? collect_list() is an aggregation function in Spark SQL and PySpark. It: Collects all values of a column (within a group, if grouped) into a single array, preserving duplicates and order (non-deterministically). ✅ Syntax In PySpark: 🧾 Example Input table: categoryvalueAxAyAxBzBy Query: Output: categoryvalue_listA[x, y, x]B[z, y] 🔄…

  • PySpark Control Statements Vs Python Control Statements- Conditional, Loop, Exception Handling, UDFs

    understanding when and why to use UDFs (User-Defined Functions) in PySpark is key for both real-world development and interviews. Let’s break it down clearly: ✅ What is a PySpark UDF? A UDF (User-Defined Function) lets you write custom logic in Python (or Java/Scala), which can then be applied to DataFrames just like native Spark functions.…

  • Pyspark Memory Management, Partition & Join Strategy – Scenario Based Questions

    Great question — PySpark joins are a core interview topic, and understanding how they work, how to optimize them, and which join strategy is used by default shows your depth as a Spark developer. ✅ 1. Join Methods in PySpark PySpark provides the following join types: Join Type Description inner Only matching rows from both…

  • Data Engineer Interview Questions Set5

    Here’s a detailed and interview-optimized answer sheet for each of your 8 questions (Q1–Q8), covering PySpark coding, Data Quality (DQ), SCD, optimization, and Spark architecture (AQE) — exactly how you’d want to respond in a technical interview: ✅ Q1. Extract dates from lines using string methods (not regex) and return those with year > 2018…

  • SQL Tricky Conceptual Interview Questions

    Perfect—now I understand! You’re looking for tricky, high-quality SQL interview questions like: “What’s the difference between DELETE, DROP, and TRUNCATE?” These are concept-based, real-world, and interview-style—not just syntax exercises. 🔥 Top Tricky SQL Interview Questions (with Answers) Below is a carefully curated list covering real-world understanding, edge cases, performance, and design: ✅ 1. What is…

  • Data Engineer Interview Questions Set4

    Perfect! Here’s everything inline, right in this window: ✅ Part 1: Spark Cluster Simulation Notebook (Inline Code) This Jupyter/Databricks notebook simulates how Spark behaves across cluster components: 🧠 Use .explain(True) at any step to inspect execution plan. ✅ Part 2: Spark Execution Flow — Mindmap Style Summary (Inline) ✅ Optional: Mindmap Format You Can Copy…

  • Data Engineer Interview Questions Set3

    Let’s visualize how Spark schedules tasks when reading files (like CSV, Parquet, or from Hive), based on: ⚙️ Step-by-Step: How Spark Schedules Tasks from Files 🔹 Step 1: Spark reads file metadata When you call: 🔹 Step 2: Input Splits → Tasks File Size Block Size Input Splits Resulting Tasks 1 file, 1 GB 128…

  • Data Engineer Interview Questions Set2

    Here’s the full code from the Databricks notebook, followed by a handy Join Optimization Cheatsheet. 📓 Azure Databricks PySpark Notebook Code 🔗 Broadcast Join vs Sort-Merge Join + Partitioning vs Bucketing ✅ Notes on Optimization 📘 Join Optimization Cheatsheet Aspect Broadcast Join Sort-Merge Join Partitioning Bucketing Trigger Small table < threshold (10MB) Default fallback User-defined…

  • What is Hive? Important Points, Interview Questions

    Absolutely! Let’s break down the different Hive Table Types, their definitions, and the key differences with practical examples and a comparison table. 🧠 Hive Tables and Their Types Hive provides logical abstraction over data in HDFS or compatible storage systems. There are 4 major types of Hive tables: 1️⃣ Managed Tables (Internal Tables) ✅ What…

  • How SQL queries execute in a database, using a real query example.

    We should combine both perspectives—the logical flow (SQL-level) and the system-level architecture (engine internals)—into a comprehensive, step-by-step guide on how SQL queries execute in a database, using a real query example. 🧠 How a SQL Query Executes (Combined Explanation) ✅ Example Query: This query goes through the following four high-level stages, each containing deeper substeps.…

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