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Expert roadmaps, tutorials, salary guides and interview prep across Data Science, Generative AI, Python, Cloud & Analytics β€” written by GloryTecks trainers in Hyderabad.

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Data Engineering
6 May 2026 7 min

CDC (Change Data Capture) Explained with Examples

What change data capture is and how it works: the problems it solves that watermarks cannot, log-based capture in SQL Server and Debezium, a working trigger-based example on the real Chinook database that replicates an insert, six updates and a delete into a copy, safe replays after a crash, and pitfalls.

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Data Analytics
6 May 2026 8 min

SQL for Data Analysts: The Queries You Need Daily

The SQL an analyst writes every day, each query run on a real sample database: profiling a table before trusting it, reconciling totals, monthly reports that keep empty months, share of total with a window, period-over-period change with LAG, new versus returning customers and the latest record per customer.

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GCP
6 May 2026 10 min

GCP Networking Basics for Data Engineers

Most data services on Google Cloud need no network setup, until a job must run on private addresses or reach a database. This guide covers VPC networks, subnets, firewall rules, Private Google Access, Cloud NAT and service perimeters, and sizes subnets for pipeline workers with a short script.

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Data Science
6 May 2026 7 min

Statistics for Data Science: The 20% You Actually Need

The statistics data scientists use constantly, each idea shown on real data in Python: when the median beats the mean, confidence intervals by bootstrapping, what a p-value does and does not say, why effect sizes matter, how testing many things manufactures findings, and how Simpson's paradox reverses a conclusion.

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Data Science
6 May 2026 7 min

SQL for Data Science: Queries Every Data Scientist Must Know

The SQL queries data scientists write every week, each run on a real sample database with its output: joining and aggregating, the join fan-out that inflated revenue ninefold, finding what is missing with an anti-join, CTEs and window functions for running totals and top-N per group, and counting around NULLs.

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Data Engineering
6 May 2026 6 min

Airflow Tutorial: Orchestrating Data Pipelines

A practical introduction to Apache Airflow: what orchestration adds to a pipeline, the scheduler, DAG processor and metadata database, a complete three-task DAG written with the TaskFlow API and run on real taxi data with dag.test, how XComs, retries and logical dates work, an idempotent rerun, and design habits.

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