IT Career Guides & Free Resources
Expert roadmaps, tutorials, salary guides and interview prep across Data Science, Generative AI, Python, Cloud & Analytics — written by GloryTecks trainers in Hyderabad.
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PySpark Tutorial: DataFrames, Transformations and Actions
A practical PySpark DataFrame tutorial on three million real New York taxi trips: declaring schemas, filtering and deriving columns with when and otherwise, grouped aggregation that exposes a trap in tip data, a join and a window function for top zones per borough, the same logic in Spark SQL, and the actions.
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.
Cloud Data Warehouses Compared: Snowflake vs BigQuery vs Redshift
Comparisons of Snowflake, BigQuery and Redshift usually focus on architecture and pricing. For the people writing queries, the dialects matter just as much. The same six queries are translated between the three here with sqlglot, revealing function differences and one silent trap: where NULLs sort by default.
Apache Iceberg vs Delta Lake vs Hudi
A comparison of the three open table formats: the problems they all solve on a data lake, Iceberg's hidden partitioning and partition evolution, Delta Lake's transaction log and Spark roots, Hudi's copy-on-write and merge-on-read tables and incremental queries, interoperability through UniForm, and a choice guide.
Data Engineer Salary in Hyderabad 2026: How the Role Pays Compared With Others
Is data engineering a well-paid role, or just a popular one? This guide answers with real 2025 survey data rather than unsourced ranges: data engineers compared with analysts, data scientists, AI/ML engineers and developers in the same country and with the same experience, and what that means for a Hyderabad offer.
Spark vs Hadoop: What Changed and Why
What changed when Spark overtook Hadoop MapReduce: the three parts of Hadoop, the MapReduce model emulated step by step on three million taxi trips with its intermediate data written to disk, why in-memory processing and DAGs mattered, what Spark still borrows from Hadoop, and what that means today.