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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 6 min

Delta Lake Explained: Reliable Lakes with ACID

Delta Lake explained with a working table built from real taxi data: what the transaction log is, how each write becomes an atomic version, schema enforcement rejecting a bad append, delete and merge, a merge that quietly re-inserted deleted rows, time travel between versions, and maintenance.

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Data Engineering
6 May 2026 6 min

Idempotency in Data Pipelines: Why It Matters

What idempotency means for data pipelines and how to achieve it: why retries and redeliveries are unavoidable, four load strategies put through a rerun and a mid-load crash on real taxi aggregates, where plain appends doubled the data and an untransacted replace exposed 47% of it, and the patterns that hold up.

GloryTecks Team
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Data Engineering
6 May 2026 6 min

Distributed Systems Basics for Data Engineers

The distributed systems ideas behind Spark, Kafka and cloud warehouses, for data engineers: partitioning and hot keys, why modulo hashing moved 74% of real taxi data when a node was added and consistent hashing 23%, replication, what CAP really says, failures and retries, and why clocks cannot be trusted.

GloryTecks Team
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Data Engineering
6 May 2026 8 min

Data Modeling: Star Schema, Snowflake and Data Vault

The three main warehouse modelling approaches compared by building each from the real Chinook database: a star with 3 tables, a snowflake with 6 and a data vault with 11, the joins the same question needs in each, why all three give identical answers, what each optimises for, and how teams combine them.

GloryTecks Team
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Data Engineering
6 May 2026 7 min

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.

GloryTecks Team
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Data Engineering
6 May 2026 6 min

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.

GloryTecks Team
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