INSERT
Darshini
The SQL INSERT command is used to add new records to a table. Whether you’re inserting single or multiple rows, data from another table, or computed values, this command is…
Darshini
Truncate
The TRUNCATE command in SQL is a Data Definition Language (DDL) operation used to remove all rows from a table, effectively resetting it to an empty state. Unlike DELETE, it…
ALTER
The ALTER command in SQL is a powerful tool used to modify the structure of existing database objects like tables, columns, or constraints. This guide explores the types of ALTER…
DROP
The DROP command in SQL is used to delete database objects permanently. This includes tables, databases, indexes, views, or constraints. Once dropped, the object cannot be recovered unless a backup…
Spark UI
Setting up the Spark History Server on an Amazon EC2 instance involves configuring the Spark History Server to track and display Spark application logs. Here’s a step-by-step guide: Prerequisites Spark…
withColumn
In PySpark, the withColumn method is used to add a new column, modify an existing column, or replace an existing column in a DataFrame. It is one of the primary…
when
In PySpark, the when function is a crucial part of the pyspark.sql.functions module that helps implement conditional logic in a DataFrame transformation pipeline. Here’s an in-depth explanation of its usage,…
Recursive cte
A Recursive Common Table Expression (CTE) is a feature in SQL that allows a query to repeatedly reference itself, is a powerful SQL feature that simplifies working with hierarchical or…
how to change a sql data type before flattening
Changing a SQL data type before flattening involves transforming the format or type of data in a column or structure to match the desired schema or processing requirements. This step…
ACID Properties
ACID properties are fundamental principles that ensure reliable and consistent transaction processing in relational databases. The term ACID stands for Atomicity, Consistency, Isolation, and Durability. These properties ensure that database…