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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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Nested and Repeated Fields in BigQuery
BigQuery can keep an order's line items inside the order's own row, as an array of structs. This guide explains nested and repeated fields, builds one from a real sample database, shows how they stop a join inflating totals nearly ninefold, and covers UNNEST, array subqueries, limits and when a join is better.
Redshift vs Snowflake vs BigQuery: A Comparison
Redshift, Snowflake and BigQuery bill for different things: running time, data scanned, capacity-hours. Pricing pages make them hard to compare. This guide prices one realistic workload in each warehouse's own unit, from documented billing rules, and shows the single setting that dominates each bill.
Streaming Data into BigQuery: A Practical Guide
Streaming new events into BigQuery is well covered. Streaming changes, where rows are updated and deleted, needs BigQuery's change data capture. This practical guide covers the pseudocolumns, primary keys, sequence numbers and max_staleness, and simulates the ordering rules to show how out-of-order changes go wrong.
BigQuery Best Practices for Analysts
An analyst can go wrong in BigQuery in three ways: a wrong number, a wasted scan, or a result nobody can reproduce. This guide gives a routine for each, with four correctness checks on 2.9 million real trips: NULL counts, filters that lose rows, days that shift with the time zone, and a join that adds rows.
BigLake and External Tables in BigQuery
BigQuery can query files where they lie, through an external table or a BigLake table. Both point at the same files; what differs is who needs access to the bucket and how finely access can be controlled. This guide explains the difference with a worked access model, the DDL, metadata caching, limits and when to load.
BigQuery Federated Queries Explained
A federated query lets BigQuery ask a live operational database a question and join the answer to warehouse tables, with no pipeline in between. This guide explains EXTERNAL_QUERY, shows on a sample database how much pushdown saves and where it stops, and covers connections, pricing, regions and when to replicate.