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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.
SQL Tricky Conceptual Interview Questions
Here’s a clear explanation of SQL Keys—including PRIMARY KEY, UNIQUE, FOREIGN KEY, and others—with examples to help you understand their purpose, constraints, and usage in real-world tables. 🔑 SQL KEYS – Concept and Purpose SQL keys are constraints used to: 1️⃣ PRIMARY KEY ✅ Example: 🧠 Composite Primary Key: 2️⃣ UNIQUE Key ✅ Example: 3️⃣…
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 a clear and structured comparison of RDD, DataFrame, and Dataset in Apache Spark: 🔍 RDD vs DataFrame vs Dataset Feature RDD (Resilient Distributed Dataset) DataFrame Dataset Introduced In Spark 1.0 Spark 1.3 Spark 1.6 Type Safety ✅ Compile-time type safety (for RDD[T]) ❌ Not type-safe (rows with schema) ✅ Type-safe (only in Scala/Java) Ease…
How SQL queries execute in a database, using a real query example.
Understanding how an SQL query executes in a database is essential for performance tuning and system design. Here’s a step-by-step breakdown of what happens under the hood when you run an SQL query like: 🧭 0. Query Input (Your SQL) You submit the SQL query via: ⚙️ Step-by-Step SQL Query Execution 🧩 Step 1: Parsing…
Comprehensive guide to important Points and tricky conceptual issues in SQL
The CASE statement is one of the most powerful and flexible tools in SQL. It allows conditional logic anywhere in your query—SELECT, WHERE, GROUP BY, ORDER BY, and especially within aggregations. ✅ General Syntax of CASE 🔍 Use Cases of CASE in Different Clauses ✅ 1. In SELECT — Conditional column values 📌 Labeling or…
RDD and Dataframes in PySpark- Code Snipppets
Where to Use Python Traditional Coding in PySpark Scripts Using traditional Python coding in a PySpark script is common and beneficial for handling tasks that are not inherently distributed or do not involve large-scale data processing. Integrating Python with a PySpark script in a modular way ensures that different responsibilities are clearly separated and the…
Azure Databricks tutorial roadmap (Beginner → Advanced), tailored for Data Engineering interviews in India
Great! Here’s how we’ll structure both: 🧪 Hands-On Databricks Notebooks (Ready-to-Use) Each notebook is short and focused on one concept, designed for execution in Azure Databricks. 📘 Notebook 1: Spark RDD Basics 📘 Notebook 2: DataFrame Basics 📘 Notebook 3: Delta Lake & Lakehouse 📘 Notebook 4: Databricks Workspace Basics 🎯 Sample Interview Questions (Conceptual…
Spark SQL Join Types- Syntax examples, Comparision
Here’s the PySpark equivalent of all 4 types of joins — inner, left, right, and full outer — with duplicate key behavior clearly illustrated. ✅ Step 1: Setup Sample DataFrames 1️⃣ Inner Join (default) ✅ Output: All id=1 rows from both sides are matched → 4 rows total. 2️⃣ Left Join ✅ Output: All rows…
DataBricks Tutorial for Beginner to Advanced
Great! Since your first topic is Data Lakehouse Architecture, the next step should build smoothly toward using Databricks practically—with cloud context (AWS or Azure). Here’s a suggested progression roadmap and what cloud-specific highlights to include at each step: 🔁 Follow-Up Sequence (Beginner → Advanced) ✅ 1. Lakehouse Basics (You’ve Done) ✅ 2. Cloud Foundation (Azure…
Complete crisp PySpark Interview Q&A Cheat Sheet
Q1.Default Sizes for Broadcast in PySpark In PySpark, broadcasting is used to efficiently share a small DataFrame or variable with all worker nodes to avoid shuffling during joins. 🔹 Default Sizes for Broadcast in PySpark The default maximum size for broadcasting is: This means: 🔧 Configurable Setting You can change this threshold via Spark config:…
Python Lists- how it is created, stored in memory, and how inbuilt methods work — including internal implementation details
In Python, a list is a mutable, ordered collection of items. Let’s break down how it is created, stored in memory, and how inbuilt methods work — including internal implementation details. 🔹 1. Creating a List 🔹 2. How Python List is Stored in Memory Python lists are implemented as dynamic arrays (not linked lists…
Data Engineer Interview Questions Set1
1.Tell us about Hadoop Components, Architecture, Data Processing 2.Tell us about Apache Hive Components, Architecture, Step by Step Execution 3.In How many ways pyspark script can be executed? Detailed explanation 4.Adaptive Query Execution (AQE) in Apache Spark- Explain with example 5.DAG Scheduler in Spark: Detailed Explanation, How it is involved at architecture Level 6.Differences between…
PySpark SQL API Programming- How To, Approaches, Optimization
📌 How to Decide Which Table to Broadcast in PySpark? Broadcasting a table eliminates shuffle operations, making joins faster by distributing a small table to all worker nodes. 💡 General Rule:📌 Broadcast the smaller table if:✔ Size < 10GB (safe limit)✔ Used in a JOIN operation✔ Frequently accessed in multiple queries 🔍 1️⃣ Automatically Decide…
How the Python interpreter reads and processes a Python script and Memory Management in Python
I believe you read our Post https://www.hintstoday.com/i-did-python-coding-or-i-wrote-a-python-script-and-got-it-exected-so-what-it-means/. Before starting here kindly go through the Link. How the Python interpreter reads and processes a Python script The Python interpreter processes a script through several stages, each of which involves different components of the interpreter working together to execute the code. Here’s a detailed look at how…