by Team AHT | Oct 6, 2024 | Pyspark
When working with PySpark, there are several common issues that developers face. These issues can arise from different aspects such as memory management, performance bottlenecks, data skewness, configurations, and resource contention. Here’s a guide on troubleshooting... by Team AHT | Oct 2, 2024 | SQL
Partitioning in SQL, HiveQL, and Spark SQL is a technique used to divide large tables into smaller, more manageable pieces or partitions. These partitions are based on a column (or multiple columns) and help improve query performance, especially when dealing with... by Team AHT | Oct 2, 2024 | SAS, SQL
This is how PIVOT and UNPIVOT work in PySpark with Spark SQL using official syntax. 1. PIVOT in Spark SQL The PIVOT operation in Spark SQL allows you to convert rows into columns based on values in a specific column. It helps to summarize and reshape the data in a... by Team AHT | Sep 6, 2024 | SQL
SQL query flows through the Oracle engine in the following steps: Step 1: Parsing The SQL query is parsed to check syntax and semantics. The parser breaks the query into smaller components, such as keywords, identifiers, and literals. Step 2: Optimization The parsed... by Team AHT | Aug 29, 2024 | Pyspark
PySpark is a powerful Python API for Apache Spark, a distributed computing framework that enables large-scale data processing. Spark was initially started by Matei Zaharia at UC Berkeley’s AMPLab in 2009, and open sourced in 2010 under a BSD license. In 2013,... by Team AHT | Aug 28, 2024 | Pyspark
PySpark, as part of the Apache Spark ecosystem, follows a master-slave architecture(Or Driver- Executor Architecture) and provides a structured approach to distributed data processing. Here’s a breakdown of the PySpark architecture with diagrams to illustrate... by Team AHT | Aug 28, 2024 | Pyspark
Yup. We will discuss- Memory Management through Hadoop Traditional map reduce vs Pyspark- explained with example of Complex data pipeline used for Both. Let’s delve into a detailed comparison of memory management between Hadoop Traditional MapReduce and PySpark,... by Team AHT | Aug 26, 2024 | Pyspark
In a complex ETL (Extract, Transform, Load) environment, the spark-submit command can be customized with various options to optimize performance, handle large datasets, and configure the execution environment. Here’s a detailed example of a spark-submit command... by Team AHT | Aug 26, 2024 | Pyspark
Deploying a PySpark job can be done in various ways depending on your infrastructure, use case, and scheduling needs. Below are the different deployment methods available, including details on how to use them: 1. Running PySpark Jobs via PySpark Shell How it Works:... by Team AHT | Aug 26, 2024 | Tutorials
Hive a Data warehouse infra Hive is an open-source data warehouse infrastructure built on top of Hadoop for providing data summarization, query, and analysis. It allows users to query and manage large datasets residing in distributed storage using a SQL-like language... by Team AHT | Aug 26, 2024 | Pyspark
PySpark scripts can be executed in various environments and through multiple methods, each with its own configurations and settings. Here’s a detailed overview of the different ways to execute PySpark scripts: 1. Using spark-submit Command The spark-submit command is... by Team AHT | Aug 24, 2024 | Pyspark
DAG Scheduler in Spark: Detailed Explanation The DAG (Directed Acyclic Graph) Scheduler is a crucial component in Spark’s architecture. It plays a vital role in optimizing and executing Spark jobs. Here’s a detailed breakdown of its function, its place in... by Team AHT | Aug 24, 2024 | Pyspark
To determine the optimal number of CPU cores, executors, and executor memory for a PySpark job, several factors need to be considered, including the size and complexity of the job, the resources available in the cluster, and the nature of the data being processed.... by Team AHT | Aug 24, 2024 | Pyspark
In PySpark, jobs, stages, and tasks are fundamental concepts that define how Spark executes distributed data processing tasks across a cluster. Understanding these concepts will help you optimize your Spark jobs and debug issues more effectively. Let’s break down how... by Team AHT | Aug 24, 2024 | Pyspark
We know a stage in Pyspark is divided into tasks based on the partitions of the data. But Big Question is How these partions of data is decided? This post is succesor to our DAG Scheduler in Spark: Detailed Explanation, How it is involved at architecture Level. In... by Team AHT | Aug 24, 2024 | Pyspark
Apache Spark is a powerful distributed computing system that handles large-scale data processing through a framework based on Resilient Distributed Datasets (RDDs). Understanding how Spark partitions data and distributes it via shuffling or other operations is crucial... by Team AHT | Aug 16, 2024 | SQL
We are to discuss these Datawarehouse terms regulary being asked in Data Related Job Interviews :-1. Data Warehouse 2. Data Mart 3.OLTP, OLAP and their differences 4.Fact and Dimension Tables 6. Difference between fact and Dimension tables 7.Star and Snowflake Schema... by Team AHT | Aug 15, 2024 | Pyspark
In Apache Spark, data types are essential for defining the schema of your data and ensuring that data operations are performed correctly. Spark has its own set of data types that you use to specify the structure of DataFrames and RDDs. Understanding and using Spark’s... by Team AHT | Aug 12, 2024 | Pyspark
In PySpark, string manipulation and data cleaning are essential tasks for preparing data for analysis. PySpark provides several built-in functions for handling string operations efficiently on large datasets. Here’s a guide on how to perform common string manipulation... by Team AHT | Aug 6, 2024 | Python
Merge sort is a classic divide-and-conquer algorithm that efficiently sorts a list or array by dividing it into smaller sublists, sorting those sublists, and then merging them back together. Here’s a step-by-step explanation of how merge sort works, along with... by Team AHT | Aug 2, 2024 | SQL
Let’s list all possible places where subqueries in MySQL or Hive QL or Pyspark SQL Query can be used: 1. In the SELECT Clause Subqueries can compute a value for each row. SELECT employee_id, (SELECT COUNT(*) FROM project_assignments pa WHERE pa.employee_id =... by Team AHT | Jul 29, 2024 | AI & ML
Data preprocessing is a crucial step in machine learning. It involves cleaning and transforming raw data into a format suitable for modeling. Data Cleaning Data cleaning involves identifying and correcting errors, inconsistencies, and inaccuracies in the data such as... by Team AHT | Jul 29, 2024 | AI & ML
In this lesson, we’ll cover essential Python libraries for machine learning: NumPy, Pandas, Matplotlib, and Scikit-Learn. NumPy NumPy is a library for numerical computations in Python. It provides support for arrays, matrices, and many mathematical functions.... by Team AHT | Jul 29, 2024 | AI & ML
What is AI? Artificial Intelligence (AI) is the simulation of human intelligence in machines that are programmed to think and learn like humans. AI systems can perform tasks such as visual perception, speech recognition, decision-making, and language translation. What... by Team AHT | Jul 29, 2024 | AI & ML
My Posts in this series will follow below said topics. Introduction to AI and ML What is AI? What is Machine Learning? Types of Machine Learning Supervised Learning Unsupervised Learning Reinforcement Learning Key Terminologies Python for Machine Learning Introduction... by Team AHT | Jul 29, 2024 | AI & ML
What is AI? Artificial Intelligence (AI) refers to the simulation of human intelligence in machines that are programmed to think and learn. These systems can perform tasks that typically require human intelligence, such as visual perception, speech recognition,... by Team AHT | Jul 28, 2024 | Python
Python provides various libraries and functions to manipulate dates and times. Here are some common operations: DateTime Library The datetime library is the primary library for date and time manipulation in Python. datetime.date: Represents a date (year, month, day)... by Team AHT | Jul 26, 2024 | Pyspark
Optimization in PySpark is crucial for improving the performance and efficiency of data processing jobs, especially when dealing with large-scale datasets. Spark provides several techniques and best practices to optimize the execution of PySpark applications. Before... by Team AHT | Jul 25, 2024 | Pyspark, SAS
Let us create a comprehensive SAS project that involves merging, joining, transposing large tables, applying PROC SQL lead/rank functions, performing data validation with PROC FREQ, and incorporating error handling, macro variables, and macros for various functional... by Team AHT | Jul 23, 2024 | Python
Error and Exception Handling: Python uses exceptions to handle errors that occur during program execution. There are two main ways to handle exceptions: 1. try-except Block: The try block contains the code you expect to execute normally. The except block handles...