# Elasticsearch Features and Practical Usage 🌊 The era of manually rotating ` is over. With data streams your app just keeps writing to the same name, and all the backing-index management is handled for you. 🏷️ Title: Data stream (logical stream for append-only time-series data) 🔗 URL: 📘 Overview A data stream is an abstraction layer that lets you address a set of indices, optimized for append-only time-series data, under a single name. It suits continuously flowing data like logs, events, and metrics — you read and write to one resource name without worrying about the hidden "backing indices" behind it. ⚙️ How It Works ・A data stream is made of multiple auto-generated, hidden backing indices. The naming is `.ds--<>-`, where the generation is a six-digit, zero-padded integer starting at `000001` (e.g. `.ds-logs-myapp-prod-2026.06.10-000001`). ・Only the most recent "write index" accepts new documents. You cannot write directly to older backing indices. ・Searches automatically route to all backing indices, so queries span the entire dataset. ・Every document needs an `@timestamp` field mapped as `date` or `date_nanos`. If the template omits it, a default `date` mapping is applied automatically. ・A matching index template containing a `data_stream` definition is mandatory; it holds the mappings, settings, and lifecycle policy. One template can be shared across multiple data streams. ・When an age or size threshold is hit, a "rollover" creates a new backing index and switches the write index. This is automated via ILM or data stream lifecycle. 🛠️ Practical Usage First, define an index template that includes `data_stream`. `PUT _index_template/logs-myapp-template` `{ "index_patterns": ["logs-myapp-*"], "data_stream": {}, "template": { "mappings": { "properties": { "@timestamp": { "type": "date" } } } } }` Then your app simply keeps writing to the same name. `POST logs-myapp-prod/_doc` `{ "@timestamp": "2026-06-10T09:00:00Z", "level": "INFO", "message": "started" }` 💡 Use Cases A common setup is writing application logs to a `logs-myapp-prod` data stream and letting backing-index rollover be managed automatically. The app no longer rotates date-based indices (` itself; it just POSTs to the same endpoint every time. ⚠️ Caveats ・Backing index names are an internal implementation detail. They can change during restore or shrink, so never build logic (like dates) off the names. ・It is a poor fit for frequently overwriting the same ID (last-write-wins); for that, use a regular index or an alias. ・Use dedicated APIs like `update by query` and `delete by query` for modifications, and remember you cannot write directly to anything but the write index. ・You cannot delete an index template that is in use by a data stream. #Elasticsearch# #DataStreams#

Arc x @chainlink: Data and Interoperability for Financial Applications Join @samconnerone and @thedavedev on August 27 at 10 AM ET for a builder-focused session on data and interoperability for financial applications on Arc: → Reliable market data for pricing, risk, and settlement → Crosschain connectivity for multichain applications → Data Streams, Data Feeds, and CCIP → Practical resources for builders getting started on Arc

JUST LAUNCHED: Chainlink TWAP Data Streams are now live powering @Polymarket's 5 & 15-min crypto markets. With $9B+ in trading volume to date, Chainlink-powered Polymarkets now leverage time-weighted average pricing for an enhanced user experience.

Real-world assets need real-time data. With @Chainlink Data Streams now live on X Layer, developers gain access to high-frequency pricing for equities, treasuries, and commodities - optimized for RWA perps and onchain finance. Read more:

TODAY: New Chainlink integrations ↓ • @dawninternet: Proof of Reserve & Data Streams to verify reserves & expand the utility of USD.infra & sUSD.infra across DeFi. • @predictdotfun: CRE & Data Streams to power new 15-min up/down markets for top U.S. equities. LINK everything.

BLOCKCHAIN EXPANSION UPDATE Chainlink services expanded across the following blockchains: CCIP • Arc • MOVA Data Streams • Arc CRE • ADI Chain • Ink • Monad Data Feeds • Arc • Tempo

Chainlink lands another DEX as Metric goes live Newly launched Metric uses @chainlink Data Streams as its price oracle, with pools that trade tokenized stocks, commodities, and other real-world assets around live reference prices. @metricxyz says it processed $10B in volume while still in stealth. The launch adds to a growing Chainlink stack on @RobinhoodCrypto's chain, where $LINK infrastructure has been the official oracle layer since day one of July's mainnet debut, and new protocols keep building on top of it.

TODAY: New Chainlink integrations ↓ • @forevermoney_ai: CCIP to expand 1:1 native TAO to Robinhood Chain • @gmtrade_xyz: Data Streams to power 24/7 commodity markets LINK everything.

Chainlink is quietly becoming prediction markets' plumbing @Polymarket's 5 and 15-minute Bitcoin markets run on Chainlink Data Streams and have already cleared over $3B in volume. @JupiterExchange, Solana's biggest DEX aggregator, plugged in the same infrastructure for its own 5 and 15-minute markets on $BTC, $ETH and $SOL. Then there's @world_xyz, the mystery Solana project that spent months as a glowing globe with zero details. It revealed itself this week live inside Phantom, reaching 20 million users and running on Chainlink for automated resolutions. Add in exclusive oracle rights for the official @FIFAWorldCup 2026 prediction market, and the pattern's clear: manual votes and social-consensus resolution are getting replaced by automated, tamper-resistant settlement. @chainlink is quietly becoming the infrastructure layer under one of crypto's fastest growing categories.

Trending this week on OKX: • Listed: $RE global Spot • Added: $ONDO $BEAT X-Perps • Live: Chainlink Data Streams on X Layer • Reward: upto 8% deposit match for EU • Celebrated: Gameday bonuses on Outcomes