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Dynamic Column Updates in EF Core Without Hand-Rolling SQL Injection
Sometimes you genuinely need the set of columns to update to be data, not code. An operator maps configuration fields to database columns, and you want to honor that mapping without redeploying every time it changes. The naive solution — build an UPDATE string from those column names — is also one of the easiest ways to hand-write a SQL injection vulnerability. This is how to get the flexibility without the hole. We'll build it up in three layers: make it work, make it safe, then count the cost. Layer 1: The dynamic update, the wrong way The tempting version concatenates column names into SQL: // DO NOT do this. var sql = $"UPDATE products SET { columnName } = { value } WHERE id = { id } " ; If columnName comes from configuration that an operator can edit, you've just made your schema writable by whoever controls that config. A value of name = 'x'; DROP TABLE products; -- is now your problem. Even "trusted" config is an injection surface the moment it flows into a SQL string. Layer 2: The same feature with EF.Property EF Core's ExecuteUpdateAsync lets you set a property by name without ever building SQL yourself. EF.Property<T> takes the property name as a string, and EF parameterizes the value and validates the property against the model: await db . Products . Where ( p => p . Id == id ) . ExecuteUpdateAsync ( setters => setters . SetProperty ( p => EF . Property < float ?>( p , columnName ), value )); This is already a different security posture: the value is a parameter, not interpolated text, and EF will throw rather than emit SQL if columnName isn't a real mapped property. But "EF will throw" is a runtime backstop, not a policy. We want to reject bad names before they reach the database, fail closed, and control exactly which columns are writable. Layer 3: Reflection as a whitelist The guard is to validate every incoming column name against the entity's actual properties, using reflection, and to keep an explicit blacklist of fields that must never be touched d
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Spring News Roundup: Point Releases of Boot, Security, Integration, Modulith and Spring AI 2.0
There was a flurry of activity in the Spring ecosystem during the week of June 8th, 2026, highlighting point releases of: Spring Boot, Spring Security, Spring Session, Spring Integration, Spring Modulith, Spring AMQP and Spring Vault; and GA releases of Spring AI 2.0 and Spring Data 2026.0.0. By Michael Redlich
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Article: Governing AI in the Cloud: A Practical Guide for Architects
In this article, the author outlines a practical approach to AI governance in the cloud, covering discovery of shadow AI, data classification at creation, IAM-based enforcement, policy-as-code, and operational controls. The article shows how organizations can embed governance into delivery pipelines, balancing security, compliance, and developer productivity without relying on manual processes. By Dave Ward
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The US Government Is Letting a Key Data Center Regulation Expire
The federal government is planning to let a rule regulating federal data center operations sunset in September with no replacement.
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Pagination records using JooqTemplate
Paginated queries with automatic total count calculation. Supports specifying result fields. public < E > LimitResult < List < E >, E > query ( Class < E > cls , LimitSelect limitSelect ) public < E > LimitResult < List < E >, E > query ( Class < E > cls , LimitSelect limitSelect , LimitRange range ) public < E > LimitResult < List < E >, E > query ( Class < E > cls , LimitSelect limitSelect , List resultFields ) public < E > LimitResult < List < E >, E > query ( Class < E > cls , LimitSelect limitSelect , LimitRange range , List resultFields ) Returns: LimitResult — contains getResult() (data list) and getTotal() (total count). Example: // Define pagination query LimitSelect limitSelect = new LimitSelect () { public SelectOrderByStep from ( SelectSelectStep select ) { return select . from ( T ( "user_table" )) . where ( jt . conditions ( "name%" , name , "birthday>=" , beginDate )); } public List < OrderField > orderBy () { return Arrays . asList ( F ( "birthday" ). desc ()); } }; // Mode 1: return all data, no total count LimitResult res1 = jt . query ( User . class , limitSelect ); // Mode 2: return limit rows, no total count LimitResult res2 = jt . query ( User . class , limitSelect , LimitRange . of ( 20 )); // Mode 3: paginate (offset starts at 0), calculate total count LimitResult res3 = jt . query ( User . class , limitSelect , LimitRange . of ( 20 , 0 )); // res3.getResult() returns data, res3.getTotal() returns total count // Mode 4: specify result fields LimitResult res4 = jt . query ( User . class , limitSelect , LimitRange . of ( 20 , 0 ), Arrays . asList ( "id" , "name" )); // LimitRange.all(): return all data, no total count LimitResult res5 = jt . query ( User . class , limitSelect , LimitRange . all ()); // Access results List < User > data = res3 . getResult (); int total = res3 . getTotal (); About the LimitSelect interface: // LimitSelect is a interface: public interface LimitSelect { // Build the FROM clause; the select parameter allows specifyi
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Anthropic Releases and Temporarily Suspends Claude Fable 5
On June 9, 2026, Anthropic launched Claude Fable 5, a model designed for long-horizon tasks, but it was taken offline shortly after due to a U.S. government export directive. It shares architecture with Claude Mythos 5, supporting extensive token usage. The model includes mandatory data retention requirements, which have affected its deployment with partners like Microsoft. By Andrew Hoblitzell
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Pooling contra una t3.micro, el día que se reventó...RDS Proxy es la salida?
Cómo un backend de FastAPI + asyncpg comparte un solo Postgres chiquito con sus propios trabajadores en segundo plano y un segundo servicio, por qué el techo de conexiones, no el CPU, es lo que de verdad le pone tope a nuestro autoescalado, la caída en el cambio de hora que nos enseñó la cuenta, y una mirada honesta a RDS Proxy como la válvula de escape (incluyendo la trampa de asyncpg que lo puede dejar sin hacer nada). TL;DR Ajuste Valor Por qué Driver postgresql+asyncpg asíncrono hasta el fondo pool_size / max_overflow 8 / 12 (20 por proceso) subido desde 3/5 después de una caída pool_pre_ping True mata los sockets muertos tras un reinicio de RDS / inactividad pool_recycle 1800 s techo duro que el pre-ping no puede cubrir Tope de conexiones de RDS ~87 (t3.micro, menos las reservadas) la verdadera restricción de todo Pruebas NullPool sin pooling entre event loops en pytest La lección que replanteó todo el problema: en un RDS chico, tu cuenta máxima de tareas la fija max_connections , no el CPU ni la memoria. Un autoescalado que ignora el presupuesto de conexiones va a escalar directito hacia QueuePool limit reached , o peor, FATAL: too many connections del mismo Postgres. El pool, y la cuenta escondida adentro de él engine = create_async_engine ( settings . DATABASE_URL , connect_args = { " ssl " : " prefer " }, # negocia TLS en RDS, texto plano en local pool_pre_ping = True , pool_size = 8 , max_overflow = 12 , # 8 + 12 = 20 conexiones por proceso pool_recycle = 1800 , ) Veinte conexiones por proceso se ven modestas hasta que las multiplicas por cada capa entre ellas y la base de datos: pool_size + max_overflow = 20 por proceso de Python × 2 trabajadores de uvicorn = 40 por tarea de Fargate × 2 durante un despliegue rolling = 80 (tarea vieja drenando + tarea nueva arrancando) + servicio de inteligencia (3 + 7) = 10 sobre la misma base de datos + alembic / ad-hoc / psql ≈ unas pocas ---------------------------------------- ≈ 87 ← el techo de la t3.micro, con ~0 de
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Surviving the region you run in: failover on Aurora DSQL, and what the demo proves
The thesis Quorum is built on is uncomfortable and true: the tools a team uses to coordinate an incident often live in the same region as the thing that is failing. When the region goes, the incident response goes with it. You are now coordinating a region outage over a status page that the region outage took down. Quorum is an incident command plane designed to survive a region loss. This post is about how the failover works, what the live demo does and does not prove, and where the survival story currently ends, because a database audience will ask all three and they deserve a straight answer. What DSQL gives you A multi-region DSQL cluster in the US set is three regions: two full regions, which for Quorum are us-east-1 and us-east-2, and a log-only witness in us-west-2 that has no cluster endpoint of its own. Both full-region endpoints present a single logical database with strong consistency, and the architecture is designed for 99.999% multi-region availability with no single point of failure and automated failure recovery . The behavior that matters for an incident tool is stated plainly in the GA announcement : applications can keep reading and writing with strong consistency even when they are unable to connect to a region's cluster endpoint, and the third region acts as a log-only witness with no cluster resource or endpoint. The survivor keeps serving; the witness holds the log so the surviving region keeps commit quorum. Quorum is, in effect, a live demonstration of that reference behavior with an incident-command product wrapped around it. Quorum's failover layer AWS's guidance for multi-region DSQL is to put routing in front of the endpoints: either DNS-based routing with Route 53, or application-level routing logic, so traffic redirects automatically when an endpoint becomes unreachable. This is laid out in Implement multi-Region endpoint routing for Amazon Aurora DSQL . Quorum, a Next.js app on Vercel, does the application-level version: it detects an
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Optimistic concurrency is the whole design: event sourcing on Aurora DSQL
Quorum is an incident command plane built on Amazon Aurora DSQL. The failover story lives in another post. This one is about a narrower question that turned out to be the foundation: when several responders write to the same incident at the same moment, across regions, during the worst minutes of an outage, how do you guarantee the record never forks into two conflicting truths. The answer is two design choices that are really one choice seen from two angles: event sourcing, and DSQL's optimistic concurrency control. The data model is append-only Quorum is event-sourced across four tables. Every state change is an immutable event appended to a log, not an in-place update. The current state of an incident is a fold over its events. There is no UPDATE incidents SET status = ... ; there is an acknowledged event, a note event, a resolved event, and the status you render is computed from them. The event's UUID is its primary key and its idempotency key at the same time. A retried write carrying the same UUID cannot double-apply: the insert collides on the primary key and becomes a no-op. That property sounds minor until you remember what kind of system this is. A tool designed to survive network failure retries writes constantly, and "the responder tapped resolve twice because the first response was slow" must not produce two resolutions. Append-only also suits the domain directly. For an incident system the audit trail is the product, not a side effect. "Who acknowledged this, at what time, and what did the timeline look like at 02:14" is a first-class question for the post-incident review and a compliance requirement in regulated environments. Event sourcing gives you that for free. It also gives DSQL a write pattern it likes, which matters more than you would expect. The stack, briefly TypeScript end to end. Kysely as a typed query builder rather than an ORM, because I wanted type safety without surrendering control of the SQL: on a distributed database the exact shap
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Don't Skip the Dataset Description (I Almost Did, and It Would've Cost Me)
Started looking for a tourism dataset on Kaggle for a new project. Found one with real UNWTO data, but it only went up to 2022 — not enough for what I wanted (post-COVID trends). Then found a better-looking one: "Global Tourism & Travel Trends (2019-2024)," 24 upvotes, great coverage range. Almost picked it on the spot. Then I actually read the full description. Turns out it's synthetic — 10,000 generated records, not real recorded stats. Had to rename the whole project: from "Travel Recovery Analysis" to "Travel Behavior & Satisfaction Trends (2019-2024)" — same dataset, just honest framing. Still great for practice: 33 features, zero nulls, covers spend, satisfaction, eco-choices, transport modes. Anyone else ever almost build a project around the wrong assumption about their data? 👀
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The Deep Mechanics of Online Bulk Deletion in PostgreSQL
MVCC, WAL, vacuum, and replication slots under sustained delete load - and how to delete billions of rows without your database noticing Most "how to delete a lot of rows" articles stop at "batch it and delete children before parents." That advice is correct, it's table stakes, and everyone already knows it. This article is about everything after that - the parts that actually decide whether your cleanup runs quietly in the background for a week or pages you at 3 a.m. with a full disk and a replica that's six hours behind. The thesis: at scale, your DELETE statement is the easy part. The adversaries are the subsystems a delete feeds - MVCC tuple versioning, the write-ahead log, autovacuum, and the replication machinery. Bulk deletion is really an exercise in flow control across those subsystems . Get the SQL right and the systems wrong, and you'll still take production down. We'll assume PostgreSQL (the internals are PG-specific), a live OLTP primary with at least one physical replica and one or more logical/CDC consumers, and a target of hundreds of millions to billions of rows across many related tables. The one paragraph of "basics," so we can move on: delete in dependency order (referencing rows before referenced rows); collect parent keys once; never rely on ON DELETE CASCADE for huge deletes because you can't throttle a cascade. Done. Now the real material. 1. What a DELETE actually costs A delete is not "remove a row." Under MVCC it's "mark a row version dead and write that fact everywhere." For each deleted tuple, PostgreSQL: Sets xmax on the heap tuple to your transaction id. The row is still physically present; it becomes a dead tuple once your transaction commits and no snapshot can still see it. Writes a WAL record for the heap change. If this is the first modification of that page since the last checkpoint, it also writes a full-page image (FPI) - potentially 8 KB of WAL for a single-row change. Touches every index. Index entries aren't removed at delet
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I Run 5M Vectors on a $6/mo Server. Pinecone Would Charge Me $210.
Six months ago I moved my RAG pipeline from Pinecone to self-hosted Qdrant. My vector search bill went from $210/month to $6.50/month. Same latency. Same recall. Here's exactly how. The Setup My app does document Q&A for legal contracts. The numbers: 5.2 million vectors (1536-dim, OpenAI embeddings) ~800K queries/month P99 latency requirement: < 50ms On Pinecone Serverless, this cost me roughly $210/month — storage plus read units plus write units for daily ingestion of new documents. What I Moved To A single Hetzner CX32 server: 4 vCPU, 8 GB RAM, 80 GB SSD €8.50/month (about $9.20) Qdrant running in Docker Automated daily backups to S3-compatible storage ($0.50/month) Total: ~$10/month. That's a 95% cost reduction. The Migration Was Easier Than Expected bash# Export from Pinecone (I used their scroll API) python export_pinecone.py --index legal-docs --output vectors.jsonl Start Qdrant docker run -d -p 6333:6333 -v ./storage:/qdrant/storage qdrant/qdrant Import python import_qdrant.py --input vectors.jsonl --collection legal-docs The whole migration took an afternoon. The Qdrant Python client is straightforward, and the API is surprisingly similar to Pinecone's. Performance Comparison I ran the same 10,000 test queries against both setups: MetricPinecone ServerlessQdrant Self-HostedP50 latency23ms4msP99 latency89ms12msRecall@100.970.97Monthly cost$210$10 The self-hosted Qdrant is actually faster because the data sits in memory on the same machine. Pinecone Serverless loads data from object storage on demand, which adds cold-start latency. When Self-Hosting Is a Bad Idea I want to be honest about the trade-offs: Don't self-host if: You have zero DevOps experience and no one on the team does You need 99.99% uptime SLA for enterprise customers Your vector count is growing unpredictably (10M one month, 100M the next) You're a team of 1-2 and every hour on infra is an hour not building product Do self-host if: Your scale is predictable (you know roughly how many vectors
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The Disk-Level Architecture of OLTP vs. OLAP
Every backend engineer has seen this happen, you build an application on a relational database like MySQL, handling thousands of concurrent transactions effortlessly. Then, the business asks for a real time analytics dashboard. But when you run an aggregation query over historical data, suddenly the database that effortlessly managed live traffic starts thrashing, evicting your working set, and dragging application performance down. This isn't a tuning problem, a missing index, or a badly written query. It’s a fundamental architectural collision. OLTP (Online Transaction Processing) OLTP encompasses nearly every concurrent digital interaction triggered across a distributed system. A user downloading a PDF, a microservice firing an automatic maintenance log, a comment on a social feed these are all transactions. Data engineers rely on OLTP systems (like MySQL or PostgreSQL) to capture these concurrent streams of interactions for creating , updating and deleting records. The Tree Based In-Place Engine To reliably capture massive volumes of transactions without corrupting data or locking up the application, OLTP systems rely on a highly optimized, row oriented architecture built around the B+ Tree. Because they must provide immediate, atomic updates to existing records, transactional databases manage state through a strict sequence of physical tree traversal and in-memory page mutation: The B+ Tree Indexing: When a transaction reads or updates id: 1, the engine traverses a B+ Tree from the root, through the branch nodes, directly to the specific physical leaf node holding that row. This O(\log n) traversal guarantees a fast, isolated point-lookup. It ensures the application always hits the single version of the row without scanning irrelevant data. The Buffer Pool & In-Place Updates: OLTP systems perform in place updates. The database pulls the exact page containing id: 1 from the physical disk into memory (the Buffer Pool). The specific row is mutated directly in RAM
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I Built a Consistent Hashing Ring in Pure Python and Finally Understood How Cassandra Distributes Data
I Built a Consistent Hashing Ring in Pure Python and Finally Understood How Cassandra Distributes Data I've been using Cassandra and Redis Cluster for years. I knew consistent hashing was "how they work." But I never truly got it until I built one myself from scratch, in pure Python, with zero dependencies. This post is about what I learned doing that. The Problem Consistent Hashing Solves Imagine you have 3 servers and 1 million keys. The naive approach: server = hash(key) % 3 . It works great until you add or remove a server. Change 3 to 4, and almost every key remaps to a different server. In a caching layer, that means near 100% cache miss. In a database, it means massive data movement. That's the problem consistent hashing solves. When you add or remove a node, only a fraction of keys move. Specifically, 1/n of the keys, where n is the number of nodes. Building the Ring The core idea: place both nodes and keys on a circular number line from 0 to 2^32 (or any large integer). To find which node owns a key, walk clockwise until you hit a node. Here's the minimal version: import hashlib import bisect class ConsistentHashRing : def __init__ ( self , replicas = 150 ): self . replicas = replicas self . ring = {} # hash -> node name self . sorted_keys = [] # sorted hash positions def _hash ( self , key : str ) -> int : return int ( hashlib . md5 ( key . encode ()). hexdigest (), 16 ) def add_node ( self , node : str ): for i in range ( self . replicas ): virtual_key = f " { node } :vnode: { i } " h = self . _hash ( virtual_key ) self . ring [ h ] = node bisect . insort ( self . sorted_keys , h ) def remove_node ( self , node : str ): for i in range ( self . replicas ): virtual_key = f " { node } :vnode: { i } " h = self . _hash ( virtual_key ) del self . ring [ h ] idx = bisect . bisect_left ( self . sorted_keys , h ) self . sorted_keys . pop ( idx ) def get_node ( self , key : str ) -> str : if not self . ring : raise ValueError ( " Ring is empty " ) h = self . _hash
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Python for Machine Learning: The Complete Roadmap Nobody Told You About
When I first started exploring Machine Learning, I made the same mistake most beginners do — I jumped straight into neural networks and model training without really understanding the Python underneath. I'd copy code from tutorials, get it running, and have zero idea why it worked. Then I started going through a structured Python-for-ML curriculum — and everything changed. This post is a distillation of that journey. If you're a CS student or early-career developer who wants to work seriously in ML/AI, here's the complete Python foundation you need — with the why , not just the what . Why Python Specifically? (It's Not Just Hype) Python isn't the fastest language. C++ blows it out of the water on speed — and I've personally used C++ for packet-capture modules in one of my ML projects. But Python dominates ML for one reason: the ecosystem . NumPy, Pandas, PyTorch, TensorFlow, Scikit-learn, Hugging Face — all Python-first. You don't choose Python for ML. The field chose it for you. Stage 1: Python Basics — The Foundation You Can't Skip Before you touch any ML library, you need these locked in. Variables and Data Types Python is dynamically typed, which feels nice at first but will bite you during data preprocessing if you're not careful. # These are all valid — Python infers the type name = " Parth " score = 8.97 is_enrolled = True year = 2025 For ML, the types that matter most are int , float , bool , and str — and knowing when Python silently converts between them (type coercion) can save you hours of debugging. Loops and Conditions — Your Data Iteration Backbone grades = [ 8.5 , 7.9 , 9.1 , 6.8 , 8.97 ] for g in grades : if g >= 8.5 : print ( f " Distinction: { g } " ) elif g >= 7.0 : print ( f " First Class: { g } " ) else : print ( f " Pass: { g } " ) Simple? Yes. But this exact pattern — iterate over a collection, branch on conditions — is the mental model for 80% of data cleaning code you'll write later. Functions and Lambda Expressions Functions are how you st
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What is the best real-time analytics database in 2026? An engineering buyer's guide
Traditional databases just can't keep up with high concurrency and low latency at the same time. The term "real-time" has become kind of meaningless. Everyone claims it, from batch-oriented cloud data warehouses to transactional database extensions. This makes picking the right architecture really hard without expensive trial and error. The best real-time analytics database in 2026 depends entirely on your workload shape. Key takeaways Real-time analytics (in this guide) = sub-second p95/p99 analytical queries on billions of rows, high concurrency , and milliseconds-to-seconds freshness . Best overall in 2026 for most workloads: ClickHouse (ingest throughput, query speed at scale, compression/TCO). Best for strictly predefined query paths via star-tree indexes: Apache Pinot . Best for time-series operational dashboards and observability: ClickHouse . ClickStack is its full observability offering for logs, metrics, and traces. Best for rigid ingestion-time roll-up aggregations: Apache Druid . Best for unified OLTP + real-time analytics: ClickHouse paired with its managed Postgres offering and native sync to ClickHouse , giving you a purpose-built OLTP engine and a purpose-built OLAP engine without rolling your own CDC pipeline. SingleStore is an alternative if you prefer a single HTAP engine for both. Traditional Data Warehouses: Snowflake and BigQuery are fine for batch BI if you already have one, but face latency, concurrency, and cost challenges under sub-second, high-concurrency workloads. Evaluate using 4 axes: ingest/freshness, latency under concurrency, TCO, operational complexity. What 'real-time analytics' means (and why warehouses and OLTP databases fail) Strict engineering thresholds define true real-time OLAP : sub-second query latency on complex aggregations, the ability to serve tens to thousands of concurrent queries per second (QPS), and data freshness measured in milliseconds to seconds. Traditional cloud data warehouses like Snowflake and BigQuery a
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Vertica vs VoltDB (Volt Active Data): Key Differences, Use Cases & How to Choose in 2026
If you're building a modern data stack that requires either high-throughput transaction processing or large-scale analytical workloads, you've likely come across both Vertica and VoltDB (now rebranded as Volt Active Data). While both are distributed relational database management systems (RDBMS), they are architected for completely opposite use cases — choosing the wrong one can lead to 10x higher costs, missed latency SLAs, and poor application performance. In this guide, we break down every key difference between OpenText Vertica and Volt Active Data, with practical examples, real-world use cases, and best practices to help you make the right choice for your team. Table of Contents What is OpenText Vertica? What is Volt Active Data (Formerly VoltDB)? Core Differences Between Vertica and VoltDB Real-World Use Cases: When to Pick Which Best Practices & Common Mistakes Conclusion & Key Takeaways References What is OpenText Vertica? OpenText Vertica (formerly Micro Focus Vertica) is a columnar relational DBMS built exclusively for analytical (OLAP) workloads, first launched in 2005. As of 2026, the latest stable version is 26.1, with native lakehouse and Apache Iceberg export support for modern data ecosystems. Core Vertica Architecture Vertica's design is optimized for fast queries across massive datasets: Columnar storage : Data is stored by column instead of row, enabling significantly higher compression ratios and faster aggregation queries that only access a small subset of columns Massively Parallel Processing (MPP) : Query execution and data are distributed across hundreds of nodes for parallel processing Dual deployment modes : Enterprise Mode : Shared-nothing architecture with data stored locally on nodes for maximum performance Eon Mode : Compute and storage separated, using shared object storage (S3, GCS, ADLS) to scale compute independently of storage for cloud workloads Projections : Physical, sorted copies of data optimized for common query patterns (ins
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PostgreSQL 22P01 Error: Causes and Solutions Complete Guide
PostgreSQL Error 22P01: Floating Point Exception PostgreSQL error code 22P01 is raised when a floating-point operation produces an exceptional result that cannot be represented as a valid number. This typically occurs during division by zero on float types, operations involving NaN (Not a Number), or arithmetic that yields Infinity . It is most commonly encountered in analytics, financial calculations, and data pipelines processing external or sensor data. Top 3 Causes 1. Division by Zero on Float Types Unlike integer division (which raises 22012 ), dividing a float by zero triggers a floating-point exception. This is especially common in ratio and rate calculations where the denominator can become zero at runtime. -- Problematic query SELECT total_sales :: float / total_orders :: float AS avg_order_value FROM daily_stats ; -- Safe fix using NULLIF SELECT date , total_sales :: float / NULLIF ( total_orders , 0 ):: float AS avg_order_value FROM daily_stats ; 2. NaN Values in Arithmetic Operations Data ingested from external systems, CSVs, or APIs may silently introduce NaN values into float columns. Once NaN participates in arithmetic, results become unpredictable and can trigger exceptions downstream. -- Detect NaN values (NaN is the only value not equal to itself) SELECT id , value FROM sensor_readings WHERE value != value ; -- Replace NaN with NULL safely UPDATE sensor_readings SET value = NULL WHERE value != value ; -- Filter NaN in aggregations SELECT device_id , AVG ( value ) FILTER ( WHERE value = value ) AS clean_avg FROM sensor_readings GROUP BY device_id ; 3. Infinity Arithmetic Conflicts Storing 'Infinity'::float or '-Infinity'::float is valid in PostgreSQL, but performing certain operations on them produces mathematically undefined results (e.g., Infinity - Infinity = NaN ), which can cascade into a floating-point exception. -- Check for Infinity values SELECT id , measurement FROM raw_data WHERE measurement IN ( 'Infinity' :: float , '-Infinity' :: float
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Kiro as AI Partner for MS SQL Server Optimization on .NET Core: Yang Biasa Berhari-hari, Sekarang Hitungan Jam
Dulu, nyari query yang bikin database spike itu bisa makan berhari-hari. Yang nyari capek, yang nge-fix juga capek. Sekarang? Hitungan jam — dan bonusnya, sambil belajar hal baru juga. Ceritanya begini. Kalau kamu pernah kerja di aplikasi yang pakai ORM (Object-Relational Mapping — semacam "penerjemah otomatis" antara code dan database), pasti familiar sama situasi ini: database tiba-tiba lambat, kamu dapet raw query yang jadi biang kerok, tapi di codebase kamu nulis pakai syntax ORM yang bentuknya beda jauh dari SQL mentah itu. Buat yang belum pernah deal sama ORM, bayangin gini: kamu nulis pesan dalam bahasa Indonesia, lalu ada "penerjemah otomatis" yang convert jadi bahasa Jepang sebelum dikirim ke penerima. Suatu hari ada masalah di pesan yang terkirim — tapi kamu cuma bisa lihat versi bahasa Jepang-nya. Nyari bagian mana dari tulisan Indonesia kamu yang bikin terjemahan-nya bermasalah? Itu effort-nya yang bikin pengen balik tidur aja. Sekarang dengan bantuan Kiro, cukup kasih raw query + akses ke codebase, dia otomatis nyari bagian mana di code yang nge-generate query bermasalah itu. Yang dulu butuh berhari-hari, sekarang bisa selesai dalam hitungan jam — dan itu baru tahap investigasi, belum termasuk fixing-nya. Ceritanya Kenapa Bisa Pakai Kiro Akhir-akhir ini lagi aktif pakai Kiro di tempat kerja. Awal tahun lalu kantor dapat credits melalui program Kiro for Startup , jadi ya sekalian dimaksimalkan. Selain buat debug dan explore query di MS SQL Server, kadang pakai Kiro juga buat analisa log AWS CloudWatch — sambil kasih context aplikasi yang running biar analisa-nya lebih akurat dan gak generic. Di tulisan kali ini, saya mau sharing gimana pakai Kiro sebagai partner beberapa minggu terakhir buat improve query performance di aplikasi .NET Core. Kenapa "partner"? Karena Kiro-nya gak boleh langsung akses ke database — jadi wajib melalui perantara saya. Kita discuss, kolaborasi, dan nge-solve bareng. Bukan AI yang dikasih tombol terus disuruh jalan sendiri. Wakt
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Why Most Sports Betting Projects Fail Before Launch (And It's Not the Algorithm)
If you've ever tried building a sports betting application, odds tracker, arbitrage scanner, value betting tool, or sports analytics dashboard, you've probably experienced the same thing: You start with the exciting part. The idea. The algorithm. The UI. The business logic. And then reality hits. The Hidden Problem Nobody Talks About Most developers assume the hardest part of a betting-related project is the prediction model or arbitrage logic. In practice, the real challenge is data infrastructure. Before your project can calculate anything, you need: Live events Accurate odds Multiple bookmakers Consistent market structures Historical updates Reliable refresh rates And suddenly your "weekend project" turns into a full-time data engineering job. The Scraping Trap Most developers begin by scraping bookmaker websites. At first it seems simple: Open DevTools Find the API request Parse the response Save the data Done, right? Not quite. Within a few weeks you'll likely encounter: Changed endpoints Rate limits Cloudflare protection Different JSON formats Missing markets Broken parsers Increased maintenance costs Instead of improving your product, you're fixing scrapers. Again. And again. And again. Every Bookmaker Speaks a Different Language Let's say you want to compare odds from five sportsbooks. You quickly discover that every provider structures data differently. One bookmaker might return: { "home" : "Liverpool" , "away" : "Arsenal" } Another might return: { "team1" : "Liverpool" , "team2" : "Arsenal" } A third one could use: { "participants" : [ "Liverpool" , "Arsenal" ] } Now multiply that problem across: dozens of bookmakers hundreds of leagues thousands of events You end up spending more time normalizing data than building features. Real-Time Data Changes Everything Many projects work perfectly during testing. Then live data arrives. Odds can move multiple times within a minute. If your system refreshes too slowly: arbitrage opportunities disappear alerts become