oracle-r2dbc VS H2

I blocked oracle.com and java.com at the firewall years ago.

You should also try to install Oracle XE Edition (which is free) and go through all the training materials found on oracle.com.

Thanks everyone for your helpful replies!! On further investigation the site I'm looking at appears to be a "DNS Hosting" site, whatever that is. So it's like "site1.site2.net", but when I take away "site1", "site2.net" automatically redirects to "oracle.com". It seems like the original site is in a kind of public graveyard and it's may be old records, not up to date ones, that were forgotten when things were moved to a new host or whatever (again, I don't have the correct words). So it's probably not as serious a security concern as if it were current information, however still seems like a breach of GDPR at least, as I'm in Europe.

Ok so I am unable to install and use java (I'm just trying to mod minecraft). My problem is that when I install the correct java I need and try to open and install files with java there is no option to open with java after installing it. Ive also tried jarfix but when I open it it says there is no java presence to fix. I've installed on my C drive didn't work on my D drive didn't work ive uninstalled and reinstalled but nothing I'm doing will work I'm unsure if it is because I'm on a laptop or if something just isnt compatible. Also when I go into command prompt and run java --version it gives me errors I have gotten a good result once however that still didn't work. Ive watched a bunch of YouTube videos to see what my problem may be. The process I'm using to install is 1. go to oracle.com 2. download java installer 3. run the installer and install java 3. try and open what I'm trying to install (curse forge) 4. usually uninstall and repeat. PLEASE I need someone's help I really want to know if I'm doing something wrong PLEASE!!!!

I installed Java on oracle.com, and followed all the instructions, I added the path to my java bin file on my environment variable path. I tested it out on cmds and it does seem like I have it, when I did java -version, it outputted

https://oracle.com/ it's easy to find (maximum just google oracle free hosting)

/Library/Java/JavaVirtualMachines is empty, no JDK installation performed from oracle.com or openjdk etc.

- Re-install the latest version of Java from the official site (oracle.com / java.com)

Oracle - Commercial

We're not to that point, so that's why you haven't had that communication. Oracle has been very upfront that closing the deal is but one step in the journey. Onboarding to their HR, their benefits, getting oracle.com email addresses, etc. will all come months later.

The URL should point to a particular comment, but HN removes fragments: https://github.com/h2database/h2database/issues/3686#issueco...

This sounds very much like the idiocy of "infosec" lunkheads who know nothing about what they're "fixing" but if an automated system tells them a CVE exists, they've absolutely got to have it "patched". They don't look into what the claims of the CVE are, or whether their specific use case is vulnerable. They don't know, they don't care, they're not even programmers. All they know is a box needs ticking.

A similar thing happened with h2database - a "security researcher" found that if you do something you're told not to do, then bad things happen.. but they demanded and got a CVE allocated anyway. Anyone who looks at it realises it's bullshit, but the mere existence of a CVE is all that matters to these idiots.

What the h2database developer said about it: https://github.com/h2database/h2database/issues/3686#issueco...

> I struggle to understand why I should feel the slightest shred of sympathy for "major corporations" that are using a volunteer-developed open-source project. Feel free to get your corporation to pay someone to deal with this, or pay for a similar commercial library.

> ...than it would be to learn the exact syntax and quirks and possibly bugs of someone else's implementation...

Yup. Also, having deep knowledge of the language is required.

SQLite's grammar is neat. Creating a compatible parser would make a fun project. Here's a pretty good example: https://github.com/bkiers/sqlite-parser (Actual ANTLR 4 grammar: https://github.com/bkiers/sqlite-parser/blob/master/src/main... )

Postgres, which tries to be compliant with the latest standards, however...

SQL-2016 is a beast. Not to mention all the dialects.

I'm updating my personal (soon to be FOSS) grammar from ANTLR 3 LL(k) to ANTLR 4 ALL().

I've long had a working knowledge of SQL-92, with some SQL-1999 (eg common table expressions).

But the new structures and extensions are a bit overwhelming.

Fortunately, ANTLR project has ~dozen FOSS grammars to learn from. https://github.com/antlr/grammars-v4/tree/master/sql

They mostly mechanically translate BNFs to LL(k) with some ALL(). Meaning few take advantage of left-recursion. https://github.com/antlr/antlr4/blob/master/doc/left-recursi...

Honestly, I struggled to understand these grammars. Plus, not being conversant with the SQL-2016 was a huge impediment. Just finding a succinct corbis of test cases was a huge hurdle for me.

Fortunately, the H2 Database project is a great resource. https://github.com/h2database/h2database/tree/master/h2/src/...

Now for the exciting conclusion...

My ANTLR grammar which passes all of H2's tests looks nothing like any of the official or product specific BNFs.

Further, I found discrepancy between the product specific BNFs and their implementations.

So a lot of trial & error is required for a "real world" parser. Which would explain why the professional SQL parsing tools charge money.

I still think creating a parser for SQLite is a great project.

H2 - Free, Embedded & Open source

H2 2.1

H2 for mocking relational database connections

It's open-source and written in Java, so you can even create custom procedures and register them straight in your application!

Firstly, let's set up a basic Spring Boot application. We can use the Spring Initializr with Spring Data JPA, H2 Database, Lombok added. H2 Database will provide us with a simple database, and Spring Data JPA will allow us to easily interact with it using Hibernate. Lombok will make it easier to write concise and readable classes.

Sorting chunks by similarity: commonly used tools don't do that. Most archive tools only sort by file type.

I wrote a tool that chunks the data (into variable-sized blocks, to re-sync if there are multiple files that have different length prefixes, but that's another story), and then sorts the chunks by LSH (locality sensitive hash). LSH is used by search engines to detect similar text. It can compress directories that contain multiple version of e.g. source code very well (e.g. trunk, branches). https://github.com/h2database/h2database/blob/master/h2/src/...

I discussed this approach with a researcher in this area in January 2020. AFAIK there is active research in this area, specially to compress DNA sequences. But he also wasn't aware of papers or research in this area for general-purpose data compression.

So, I think this area is largely uncharted. I would be interested (as a hobby side project) to help, if somebody is interested.