by lochan2014 | Oct 11, 2024 | Pyspark
Q1.–We are working with large datasets in PySpark, such as joining a 30GB table with a 1TB table or Various Transformation on 30 GB Data, we have 100 cores limit to use per user , what can be best configuration and Optimization strategy to use in pyspark ? will... by lochan2014 | Oct 11, 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 lochan2014 | 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 lochan2014 | Oct 2, 2024 | SAS, SQL
PIVOT Clause in Spark sql or Mysql or Oracle Pl sql or Hive QL The PIVOT clause is a powerful tool in SQL that allows you to rotate rows into columns, making it easier to analyze and report data. Here’s how to use the PIVOT clause in Spark SQL, MySQL, Oracle... by lochan2014 | 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 lochan2014 | 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 lochan2014 | 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. At First Let us go... by lochan2014 | 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 lochan2014 | 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 lochan2014 | 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 =...