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jloracle.bsky.social
Nearly-retired Oracle performance specialist. 50 years using computers, 40 years self-employed, 35 years as a freelance Oracle specialist.
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a quite common pattern: X: What is the best partition schema for my Table Z? it will become huge! Y: it depends on your ILM definition as well as the most important access patterns. X: ??? Y: ¯\_(ツ)_/¯

submitted 2 hours ago • 2 comments

Started chitting my first batch of seed potatoes last night. Charlotte as the family favourite and Purple Rain as an experimental choice - it sounds almost as if it's the result of crossingn a potato with red cabbage to get the anthcyanins (?) and colouring.

submitted 1 day ago • 0 comments

Here's the answer to a question that still re-appears from time to time. Nearly my oldest golden oldie: whe "NOT IN" is not the exact opposite of "IN". jonathanlewis.wordpress.com/2007/02/25/n...

submitted 2 days ago • 1 comment

I've just written a nice little abstract for #POUG2025. On my favourite topic: how to notice what a (run-time) execution plan is telling you. Give it a couple of days for polishing, then I'll upload it. @pougorg.bsky.social

submitted 2 days ago • 1 comment

Have you noticed that when you decide to cancel a tweet (here on Bluesky) you get a pop-up that asks you if you want to cancel the cancel (or discard the tweet). Not entirely intuitive, that. I keep hitting cancel at that point because I really meant cancel the first time around.

submitted 2 days ago • 0 comments

The effects of preparing the ground: First dig-over to remove couch grass and bindweed roots, I took about 45 - 60 minutes per sq m. Today, digging in the 100Kg of manure that I'd spread a couple of weeks ago, I managed 18 sq. m in 40 minutes.

submitted 2 days ago • 0 comments

Just noticed that the SCALE option on CREATE SEQUENCE has changed in 23c. The scale prefix used to be fixed at 6 digits by left padding mod(session_id,1000) with zeros and prepending mod(instance_id,100) + 100 (or left padding and sticking a 1 on the front). 23c drops the "+100", leaving 4/5 digits

submitted 3 days ago • 0 comments

There's been a bit of a gap since I last published a whole new note on the blog, but I've just avoided a completely empty February with a note on lightweight comment on cloning tables that hold virtual columns. jonathanlewis.wordpress.com/2025/02/24/v...

submitted 3 days ago • 1 comment

1/2 Is anyone seeing "eventual consistency" effects in the Oracle Forums (not the MOSC one). Twice in the last couple of days I've posted a comment which vanished, despite the summary reporting my name as "most recent post, a few seconds ago". Then, some minutes later, the post has appeared tbc ...

submitted 6 days ago • 1 comment

Food labelling is so dishonest oracle-base.com/blog/2025/02...

submitted 7 days ago • 1 comment

Note (not only) to self: Whenever applying an optimizer patch, check if new _fix_control values exist and if you should enable them. README do not always tell about its existence

submitted 6 days ago • 0 comments

Odd little detail I hadn't noticed before. File Explorer (in W10) doesn't seem to sort file names alphabetically. For longer names starting the same way it looks as if the sort is by name length THEN alphabetically, e.g: statnames_9208.txt statnames_18300.txt statnames_21300.txt statnames_191100.txt

submitted 7 days ago • 1 comment

Today is the day to get the asparagus going. Remove the weed-suppression sheet, top dress with a handful of high-K feed, then cover with compost to a depth of 5cm.

submitted 9 days ago • 0 comments

Fresh post! I still think people don't realise what a total game changer our macro feature is. connor-mcdonald.com/2025/02/19/c...

submitted 9 days ago • 0 comments

A recent question on the Oracle customer forum (SQL and PL/SQL) resulted in me rediscovering a note I wrote a few years ago about the validate_conversion() function and the "on conversion error" extension that appeared in 12c for conversion functions: jonathanlewis.wordpress.com/2020/04/24/c...

submitted 9 days ago • 0 comments

Game changer: maintaining an Oracle Database transaction over multiple sessions (or REST API requests!) with Database 23ai. www.thatjeffsmith.com/archive/2025...

submitted 15 days ago • 0 comments

It looks like we've acquired a family of Greater Spotted Woodpeckers ( www.rspb.org.uk/birds-and-wi... ), one has been coming to the bird feeders every morning, and we've seen it occasionally through the day.

submitted 17 days ago • 1 comment

Funny how revisiting an old note can prompt a new thought. The push_having_to_gby() hint changes execution plans, and seems to be obeyed (some of the time), but it's not actually an optimizer hint (apparently): See the Feb 2025 update at the end of: jonathanlewis.wordpress.com/2020/01/03/p...

submitted 17 days ago • 0 comments

Went to a terrific lecture at Barnard's Inn Hall (@greshamcollege.bsky.social) by Prof. Alain Goriely FRS (Gresham Professor of Geometry) on the brain: "Network and Communication" Pt. 3 of a series of (at least) 6 installments. The first 3 are available online: www.gresham.ac.uk/speakers/pro...

submitted 22 days ago • 0 comments

It's worth reminding people about some of the details of using the memory_target (rather than sga_aggregate_target and pga_aggregate_target) on huge pages and memory maps in Linux: jonathanlewis.wordpress.com/2021/08/05/m... (The topic got a mention on the MOSC forum a couple of days ago.)

submitted 26 days ago • 1 comment

Another day to mark in your calendars: #POUG2025 CfP opens on February 1st! Stay tuned. 🙌

submitted 43 days ago • 0 comments

This one's a real golden oldie that I've just rediscovered by accident. It's a reminder about how important it is to be fussy about data definitions: jonathanlewis.wordpress.com/2015/11/03/n...

submitted 27 days ago • 0 comments

A golden oldie here for anyone who's thinking about converting there database to use max_string_size = extended. There are traps you might overlook: jonathanlewis.wordpress.com/2016/02/11/q...

submitted 27 days ago • 1 comment

Went to a very entertaining talk on statistics (not Oracle ones) last night. The "Rate your experience" email that followed was accurate in its "This will only take one minute" claim. Massive oversight, though; the "what was the best bit" question didn't include the option: "The content".

submitted 27 days ago • 0 comments

Spent a couple of hours this afternoon pruning the wisteria (is it one of those self-plural words?). Managed to sort out the bottom half of the main one, and most of the low ones, but tomorrow might be ladder time.

submitted 27 days ago • 1 comment

Yet another thing that can be declarative rather than trigger-based. Good Thing™️

submitted 31 days ago • 0 comments

Went to see "Maria" last night - the last days of Maria Callas, starring Angelina Jolie. Fantastic film: excellent balance between hope, despair, memory, delusion and hallucination, backed by incredible music. Terrific supporting performance from Pierfrancseco Pavino

submitted 42 days ago • 0 comments

Golden oldie time - here's one that came to my attention because of a recent question on MOSC. Can you find the statement that triggered the dump to the alert log when a statement has triggered "too many parse errors": jonathanlewis.wordpress.com/2017/10/06/1... Something's changed by 23.4, though.

submitted 43 days ago • 0 comments