WBWalid Bensalehindatakickstart.hashnode.dev·Sep 24 · 2 min readSQL for Beginners: Stop Confusing WHERE and HAVING (With Clear Examples)If you are learning SQL, the difference between WHERE and HAVING is one of the easiest concepts to mix up—and one of the most common technical interview questions for entry-level data roles. Both clau10
KSkiran sabneinkiransabne.dev·Sep 18 · 3 min readPostgreSQL Nested Loop: When Is It Actually a Problem?PROBLEM A Nested Loop join runs its inner side once per row on the outer side. That's the cheapest possible join when the outer side is small — and a real cost multiplier once it isn't. The operator i10
PDPriyansh Dimriinpriyanshdimri.hashnode.dev·Jul 21 · 5 min readWhy GistDB Stops Optimizing EarlyMost query optimizers sit somewhere between two extremes. One extreme applies very few optimizations. Every scan reads every column, predicates stay where they were written, and joins are not reordere10
BKBalaji Kottanaindatanarratives.hashnode.dev·Jul 4 · 14 min readSnowflake Clustering: When It Saves Money, When It Costs YouPlatform: Snowflake Topics: Clustering · Cardinality · Multi-column clustering · ROI analysis · Multiple non-correlated query patterns · FinOps The honest framing before we start Clustering is not a 10
RKRakesh Kishoreintunedinstance.com·Jun 16 · 8 min readManaging Parameter Sniffing: Overcoming the Silent Execution Plan SaboteurEvery experienced database professional has faced this exact production mystery: A core application query or stored procedure that has run flawlessly for months suddenly slows to a crawl, triggering w00
RKRakesh Kishoreintunedinstance.com·Jun 14 · 9 min readMastering Execution Plans: How to Read a Query MapYou are a Junior DBA, and you just finished setting up an Extended Events session to capture long-running production queries. You open your capture file and immediately find a massive, resource-heavy 00
BPBharani Preetham Perakainbytebharani.hashnode.dev·May 14 · 1 min readOpening a form based on user filters in D365FO Using X++ and Query ClassesIf let's say there is a requirement to show a filter query where user can add different ranges he wants and once he clicks 'Ok', based on the query selected by user, the form should render. Or let's s00
IAIkem Adainviolacordis.hashnode.dev·May 5 · 7 min readInside the Query Optimizer: How Databases choose and Evaluate Query PlansYou write a query. The database runs it. You get your result. Simple, right? Not quite. Before your query ever runs, the database is already making decisions behind the scenes. It evaluates different 00
IAIkem Adainviolacordis.hashnode.dev·May 4 · 6 min readHow to Read Query Execution Plans and Fix Slow QueriesYou run a query, and it feels slow. You tweak the SQL. Add a condition. Rearrange a join. Sometimes it helps. Sometimes nothing changes. At this point, many developers are guessing. But the database i00
IAIkem Adainviolacordis.hashnode.dev·May 4 · 4 min readWhy Some Queries Are Fast and Others Are Slow.You run a query, and it works. Everything feels fast and responsive. Pages load quickly, dashboards update instantly, and there is no reason to worry. But as your data grows, things begin to change. A00
