Understand how SQL UNION and UNION ALL combine rows from compatible SELECT queries, remove or preserve duplicates, and sort the final result.
SQL UNION vs UNION ALL: Combine Query Results and Handle Duplicates Read More »
Learn the basics of Python testing with pytest by building a discount calculator, writing unit tests, following naming conventions, and running test suites.
Testing Python Code with pytest: A Beginner’s Guide Read More »
Configure Terraform remote-exec to run ordered commands on a newly created EC2 instance, then use terraform_data triggers to rerun remote validation when the server or deployment version changes.
Terraform Provisioners: Using remote-exec Over SSH Read More »
Learn to combine PowerShell pipelines, Where-Object, and ForEach-Object to filter services and preview actions safely.
PowerShell Pipelines and ForEach-Object: Filter and Process Services Read More »
Learn how to capture command output in Bash using modern command substitution, then use it for timestamps, reports, and automated backup filenames.
Bash Command Substitution: Use Command Output in Scripts Read More »
Learn the structure of SQL CASE expressions and use them to classify orders by shipping region, status, and revenue level without changing stored data.
How to Use CASE Expressions in SQL Read More »
Discover how Python context managers simplify resource cleanup and database transactions. This tutorial uses SQLite, `contextlib.closing`, and custom context managers to safely commit, roll back, and close connections.
Python Context Managers: Safely Manage SQLite Transactions with `with` Read More »
Learn to filter PowerShell objects with Where-Object using properties, comparison operators, dates, and multiple conditions in administrative data.
How to Filter Objects with Where-Object in PowerShell Read More »
Build safer Bash deployment scripts by parsing short options with getopts, validating option values, handling errors, and processing positional service names.
Parsing Bash Script Options with getopts Read More »
Build readable, multi-stage SQL queries with Common Table Expressions. This tutorial covers CTE syntax, chained aggregations, reusable query stages, common mistakes, and performance considerations.
How to Use SQL Common Table Expressions with WITH Read More »
