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I recently commented on Jonathan Lewis’s blog, Savepoint Funny , where I compared how PostgreSQL handles uniqueness differently: “PostgreSQL resolves uniqueness through heap tuple visibility". This deserves a more detailed explanation. In Oracle, unique indexes store unique entries because the B-tree key is the index key, preventing duplicates. Non-unique indexes add the ROWID to ensure that all entries are physically unique, even when indexed column values are duplicated. In PostgreSQL, all indexes, even unique ones, created explicitly by CREATE UNIQUE INDEX or implicitly to enforce a unique constraint, behave like non-unique indexes by appending the TID (tuple ID, similar to Oracle's ROWID) to the index key. This indicates that the index itself doesn't guarantee physical uniqueness, allowing multiple entries to have identical logical keys but point to different heap tuples. The actual uniqueness verification occurs at the heap level, not within the index entries. Initially, this might seem unusual—a unique index that permits duplicates. However, PostgreSQL requires this because of its MVCC system. MVCC allows duplicate entries to coexist in an index, since they can represent different versions of the same logical row. Still, PostgreSQL must guarantee that no MVCC snapshot views two rows with the same index key. Oracle doesn't face this issue because its MVCC implementation also versions index blocks, allowing a single index version to maintain unique keys. Let’s show that. Page inspect In PostgreSQL, the heap contains the table data, and index entries point to heap tuples. Visibility depends on the heap header, especially the transaction information. Index scans often visit the heap pages to check visibility, except for index-only scans, which use the heap's visibility maps as an optimization. B-tree indexes can store entries for multiple versions of the same logical row, including versions that are no longer visible to current snapshots. To ensure uniqueness, the

Originally published on MRTD.NET — fast, sourced news on crypto security, cyber & SEO. The uncomfortable first lesson You built a clean site, submitted a sitemap, maybe pinged IndexNow — and Google still shows nothing. Here's the part most guides skip: getting indexed by Google and getting indexed by everything else are two different problems , and conflating them wastes weeks. We separate what actually moves Google in 2026 from the folklore that just feels productive. Bing, Yandex and ChatGPT are the easy half If you've set up IndexNow , you've largely solved discovery for Bing, Yandex, Naver, Seznam and Yep — you POST your new/changed URLs to one endpoint and they get notified instantly. And because ChatGPT Search retrieves from Bing's index , confirmed Bing indexing effectively gates your visibility in ChatGPT's web results. That's a big chunk of the modern search surface handled with one integration. The catch: Google does not use IndexNow. It has said so repeatedly. So every "instant indexing" claim that leans on IndexNow is talking about Bing's world, not Google's. For Google, you need different levers. What actually gets you into Google There are really only two fast paths, plus one slow one. 1. Google Search Console — the only direct lever. Verify your domain (a private DNS TXT record; it does not trigger penalties or "re-evaluation," a common fear), submit your sitemap.xml , then use URL Inspection → Request Indexing on your key pages. There's a soft daily cap (~10–12 URLs), so spread a new site's pages over a few days. GSC is also the only place you can see whether a domain carries an inherited problem — essential if you bought an aged or expired domain. 2. Links on pages Google already re-crawls hourly. Googlebot's crawl budget for a brand-new, zero-authority domain is tiny. The fastest way to get a new URL discovered is a link to it from a page Google visits constantly — Reddit, Hacker News, Medium, established communities. These links are usually nofoll

The most AI-obsessed firms are spending roughly $7,500 monthly per employee on AI, per Ramp AI Index. That's not more than an engineer's salary — yet.

I'm sure many of you have experienced the frustration of publishing a new blog post only to find it's not immediately visible in search engine results. I recently learned that search engines like Bing and Yandex offer a way to quickly notify them of new posts via the IndexNow API. So, I decided to integrate this feature into my blog. Attempts and Pitfalls Initially, I created helper functions in services/indexnow_service.py to call the IndexNow API when a post was published. I structured the code to use asyncio.create_task to send a ping asynchronously whenever the post status changed to 'published' in the BlogRepository.update_status method. # services/indexnow_service.py (partial) import asyncio import httpx async def ping_urls ( urls : list [ str ], api_key : str ): async with httpx . AsyncClient () as client : for url in urls : try : response = await client . post ( " https://api.indexnow.org/submit-url " , json = { " url " : url , " key " : api_key } ) response . raise_for_status () print ( f " Successfully pinged { url } " ) except httpx . HTTPStatusError as e : print ( f " Error pinging { url } : { e } " ) except Exception as e : print ( f " An unexpected error occurred for { url } : { e } " ) async def ping_blog_post ( post_url : str , api_key : str ): await ping_urls ([ post_url ], api_key ) # BlogRepository.update_status (partial) async def update_status ( self , post_id : int , new_status : str ): # ... existing logic ... if new_status == ' published ' and INDEXNOW_KEY : post = await self . get_post_by_id ( post_id ) # In reality, you'd get the URL from the post object asyncio . create_task ( ping_blog_post ( post . url , INDEXNOW_KEY )) # ... I also created an admin API endpoint to manually trigger pings. I set up the public/<KEY>.txt file and even configured middleware. But to my surprise, the pings just wouldn't go through, no matter what I tried. After about three hours of debugging, I discovered that the ownership verification file required by the In

It is one thing to say AI will change the world. It is another to expect the class of 2026 to applaud it. In fact, when former Google CEO Eric Schmidt told University of Arizona graduates that their task is to help shape AI, he was met with a resounding chorus of boos. “I can…