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Take it away, cheeky British person:

Not the Bee

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Are you really a startup if you don’t use Slack? It’s a question that’s been asked before. Startups, specifically tech startups as that’s what this article is about, often use particular software and tools to make life easier for the team and day-to-day running of the business.

If you are a startup that’s looking to improve its work efficiency, consider using one or more of the tools listed below.

Commonly Used Startup Tools

There is an abundance of software and tools on the market for startups to use. There’s no way we’re going to be able to look at them all in any kind of article. So, to consider some software as examples, these are some of the tools that are most commonly used.

1. Slack

Slack is one of the most common tools in the tech world. Everybody uses Slack from startups to YouTube teams.

The tool is for communication within your organization. Slack works as a channel-based messaging platform for organizations to use in order to improve communications. You can direct message other team members, and send messages to larger groups.

Related: What Is Slack and How Does It Work?

The tool is perfect for making it easy to talk to teams and staff instantly, without the need for emails. Slack also supports the integration of other software and tools so that you can have all of your workplace tools in one space.

For example, you can integrate your calendar so you can send reminders in messages about upcoming events or meetings. You can even integrate services like Google Drive to create Google Docs without leaving your Slack workspace.

2. Asana

Asana is a team and task management tool. Using the platform, you put tasks on To-Do lists for different teams. From here, you can assign tasks to certain team members, and set deadlines as well.

The tool makes it much easier for teams and management to keep on top of projects and tasks so that there’s less need for catch-ups. Reporting tools on Asana make it easy to see exactly what your teams have been getting up to, as well as the to-do list style making it easy for team members to keep track of their tasks.

3. Monday

Monday is another task management tool. The platform offers a very simple yet effective solution to task management. There are plenty of reasons that teams use Monday.

Uploading tasks in a to-do list style makes it easy to break larger projects down into smaller tasks. Monday uses a color-based status to monitor the progress of tasks with just a glance. The platform also allows for integrations with other tools to bring tasks directly to you without the need for manual input, saving time.

4. Intercom

Intercom is one of the most popular live chat platforms for companies to use on their website. Most websites use live chat now as it’s a quicker and more convenient way for users to contact the support team.

This tool probably has some of the most customizable and intuitive features. Not only can you build a live chat system with automation and a bot, but you can also use Intercom to communicate via email, and build a FAQ page for your website.

5. Zendesk

Zendesk is one of the tools available that does the most for a company. The platform has an all-in-one feel to it, and can often be used to cover the whole of the customer services team.

With Zendesk, you can add live chat to your website, manage and ticket your emails, build and upload an in-depth FAQ page, manage phone calls, and manage social media. With all the important customer communication channels being brought under one roof, a team can respond to users faster than ever.

6. Google Workspace

Google Workspace is the most comprehensive tool on this list. However, this is a platform that many users may not know a company actually uses.

The platform brings Google to your organization. Google Workspace allows you to create email accounts using your company’s domain name and turns these into private Google accounts.

Related: The Best Google Teamwork Tools for Online Collaboration

This gives you access to all the Google services such as Drive, Docs, Slides, Photos, and all the others while allowing the company to manage each account.

Many organizations use Google Workspace behind the scenes for their emails, and file storage on the cloud.

How Many Startups Actually Use These Tools?

When it comes to how many startups use productivity tools, you’d probably argue that every startup does to one level or another. All startups use email at the very least, so their email client makes at least one tool that the company is using.

In terms of the list we’ve focused on in this article, all these tools are widely used by startups. Slack is used by 750,000 companies (2020), Asana by 50,000 (2018), Monday by 100,000 (2020), Intercom by 30,000+ (2021), Zendesk by 150,000 (2020), and G Suite by 6 million (2020). Across the board, the six tools we’ve looked at are used by approximately 7.1 million organizations.

And these six tools are just some of the most popular platforms out there. There are hundreds of other tools out there with high user numbers as well. So, when you consider this, inarguably you can see that so many startups really do use these tools.

So Are You Really a Startup?

Using or not using certain software cannot determine whether or not you are a startup company. The definition of a startup is "A newly established business".

If a company meets that definition, they are literally a startup. But, when you consider how integral many of these tools have become for startups, you must wonder what they’d do without them.

Ultimately, the tool that will be talked about is one that helps to increase their bottom line, improve the overall experience at work, and contribute to seamless team collaboration.

MUO – Feed

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class PostData extends DataTransferObject
{
    /** @var string */
    public $title;
    
    /** @var string */
    public $body;
    
    /** @var int */
    public $author_id;
}

$postData = new PostData([
    'title' => '…',
    'body' => '…',
    'author_id' => '…',
]);

$postData->title;
$postData->body;
$postData->author_id;

use Spatie\DataTransferObject\DataTransferObject;

class PostData extends DataTransferObject
{
    public string $title;
    public string $body;
    public int $author_id;
}

// Named arguments FTW
$post = new PostData(
    title: 'Hello World',
    body: 'This is a test post.',
    author_id: 1
);

echo $post->title, "\n";
echo $post->body, "\n";
echo $post->author_id, "\n";

$post = [
    'title' => 'Hello World',
    'body' => 'This is a test post.',
    'author_id' => 1,
];

$someObject->doStuff($post);

function doStuff(array $post)
{
    $title = ucwords($post['title']);
    $author = findAuthorById($post['author_id']);

    echo $title, "\n";
    echo htmlspecialchars($post['body']);
    echo $author['name'], "\n";		
}

function doStuff(array $post)
{
    if (empty($post['title'])) {
        throw new \Exception('Missing title');
    }

    if (empty($post['body'])) {
        throw new \Exception('Missing body');
    }

    if (empty($post['author_id'])) {
        throw new \Exception('Missing author_id key');
    }
    
    $title = ucwords($post['title']);
    $author = findAuthorById($post['author_id']);

    echo $title, "\n";
    echo htmlspecialchars($post['body']);
    echo $author['name'], "\n";		
}

function doStuff(PostData $post)
{
    $author = findAuthorById($post->author_id);
    
    echo $post->title, "\n";
    echo htmlspecialchars($post->body);
    echo $author->name, "\n";		
}

Laravel News

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Few things in life dominate their purpose of existence quite like the A-10 Warthog and its GAU-8 Avenger 30mm Cannon. The two remain forever, intrinsically linked in military lore. From tanks to terrorist convoys, the 30mm round simply decimates everything in its path. In a word, it is glorious. So BRRRRRRRT! Let’s watch how this marvel of military might works in action.

RELATED STORY

SIG Sauer NGSW: US Army Receives Final Delivery of Complete System

GAU-8 Avenger 30mm Cannon

YouTuber 3D Mil-Tech posted an awesome animation recently of the GUA-8 Avenger. And the stellar video makes it at once clear, this isn’t a gun, it’s a machine. The behemoth aircraft cannon weighs in at 619.5 pounds, measuring nearly 20 feet down the belly of the beast that is the Warthog. The 90.5-inch barrel weighs a massive 71.2 pounds.

It spits out massive 30mm rounds at a whopping 4,200 rpm. The tank buster sends rounds downrange at 3,500 fps. And the maximum effective range extends to 3,660 meters.

Certainly, the U.S. military inventory commands more impressive firepower. But when combined with the unique flying ability of the A-10, the GAU-8 Avenger excels. The combination famously busted more than 900 Iraqi tanks in Desert Storm. Timeless footage abounds of the Warthog slowly crawling across the sky, reigning fire down on enemy material and emplacements.

The Avenger employs Armor Piercing Incendiary (API) rounds. Loaded with depleted uranium, these bad boys hit like the proverbial hammer of Thor. Ultimately, few enemy tanks or positions can withstand the punch of the A-10 Warthog and the GAU-8 Avenger.

The original contract specifications called for the cannon to be capable of destroying a wide variety of targets expected during a close air support mission. It must destroy light, medium and heavy tanks, armored personnel carriers and fixed or mobile artillery. It would also need to take down hardened targets, including bunkers.

At various times, the military expressed interest in moving on from the Warthog. But then we get into a fight, the combination proves its mettle all over again. Long live the GAU-8 Avenger!

The post WATCH: How an A-10 Warthog GAU-8 Avenger 30mm Cannon Works appeared first on Tactical Life Gun Magazine: Gun News and Gun Reviews.

Tactical Life Gun Magazine: Gun News and Gun Reviews

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If you’ve wandered into the gun store recently, you might have noticed it looks a little different.

Among the rows of black handguns and FDE colored rifles, pinks, purples, and teals peer out from the gun case. Bedazzled ear pro, lacey holsters, and other feminine accessories line the shelves.

While the gun industry often looks to capitalize on new shooters, one demographic in particular is getting a lot of attention — women.

But what shaped this dramatic increase in female gun owners?

Gun Ownership Among Women

According to a Pew Research Center survey, in 2005, women accounted for only 13% of American gun owners.

By 2020, that number almost doubled, with women representing nearly 25% of gun owners in the United States.

Female gun owners are considered the fastest-growing demographic in the gun world.

But female gun ownership looks different than that of men.

On average, women opt into guns later in life. Women, on average, buy their first gun around the age of 27. In contrast, the average age for a man’s first gun is 19.

Self-defense is the most cited reason for gun ownership for both sexes. However, men typically list recreation, competition, or hunting alongside defense as reasons for purchasing firearms.

On the other hand, self-defense can often be the only reason for gun ownership among women. 27% of female gun owners say they have no further interest in firearms outside of personal protection.

In the U.S., 19.3% of women experience rape while 43.9% face sexual violence other than rape. With more than half of adult women living alone in the U.S., it’s no surprise women stock up on safety tools.

And firearms offer a solution.

“It’s a very helpless feeling knowing you can’t protect yourself or your family,” Terry Marsh told News & Observer after an intruder almost entered her home at 1 a.m. “If I had a gun or a way to protect myself, it would have given me a little bit of power, and I’d have felt secure.”

Marsh later went out and purchased her first handgun.

She’s not alone.

Women’s centric shooting organizations like The Well Armed Woman and A Girl & A Gun aim to encourage new shooters. They offer an alternative to all-male ranges and classes. Ultimately, these organizations emphasize safety thorugh training and education.

A Girl & A Gun boasts over 6,000 members with chapters in almost every state. The group noted a significant increase in interest and participation…especially in 2020.

Pandemic, Protests, and 2020

2020, a year renowned for COVID-19 and heightened social tensions introduced more Americans to guns, gear, and ammo.

The FBI recorded over 39 million background checks for firearms in 2020. Just months into 2021, that number already sits at 12 million.

But in a time where gun sales remained at an all-time high, not all gun purchases were made by men.

In fact, women accounted for 40% of gun purchases in 2020.

Even gun organizations experienced this influx, with A Girl & A Gun’s membership spiking over 150% just by July 2020.

An examination of its new members showed that while most grew up in a home without guns, the fear of civil unrest pushed them to reconsider a gun-free home.

Kathryn, a woman from Texas, was one such gun owner. A trauma surgeon and admittedly anti-gun, she said the pandemic and unrest was a contributing factor in her decision to purchase a firearm for the first time.

“I’m a trauma surgeon and have treated a fair share of gunshot victims in Chicago and Houston. I have been pretty ‘anti-gun’ as a result up until COVID,” she told surveyors with A Girl & A Gun. “At that point, I figured I might as well get comfortable with at least handling firearms in case I had to use one.”

Instructors and educators also faced an influx of new shooters signing up for classes, including the female demographic.

“We are seeing single moms, the elderly, and most surprising is middle age couples that have never seen the need to be armed,” said GW Ayers III, chief operating officer at Rainier Arms Firearms Academy, the training unit of Wichita, Kansas-based Rainier Arms Group.

In 2020, Rainier says enrollment for its CCW courses jumped 50%.

Cherie Hicks, a 58-year-old mother and yoga instructor from California told Pew Pew Tactical that though she is an experienced shooter, she plans on “amping up” her training.

“After the rioting and the looting started, that was it,’’ Hicks explained.

Though COVID-19 vaccinations are rolling out and riots have calmed, gun sales haven’t slowed down — nor does it look like they will.

The National Shooting Sports Foundation’s Mark Oliva said with enhanced gun laws potentially on the horizon, Americans continue to stock up — women included.

“It is clear that firearm sales in March were driven by gun control calls from politicians to ban entire classes of firearms and enact onerous gun laws,” Oliva told CNN Business.

Evolving Industry

With estimates in the millions, more and more American women are entering the gun community. While some bemoan the use of pinks and purples in gun stores, experts say it’s imperative the industry encourages ladies.

“Women are making a difference in the world of firearms,” Carrie Lightfoot, founder of The Well Armed Woman, said. “I believe there is no denying that women are here to stay and, therefore, need the industry to continue to understand who they are and what they want.”

And the industry seems to be trying. Every day more accessories aimed at women sprout up in online stores. Even more encouraging, women-owned brands continue to enter the firearms landscape. These niche businesses specialize in firearm-themed gear apparel and accessories for women.

This approach is smart, according to Lightfoot’s data. Her small sampling of 5,000 women revealed ladies poured over $3.5 million into guns in 2019.

“The female market offers enormous potential and dollars to the firearms industry,” Lightfoot said.

The earning potential for gear, guns, and accessories marketed towards women is endless, so long as the industry is willing to provide intelligent, safety-conscious designs.

Conclusion

Armed with cash and willing to invest in their safety, female gun owners represent a fast growing subset of the gun community.

As long as the industry continues to support women through education, training, and gear, there are no indications lady shooters will slow down any time soon.

What are your thoughts on female gun ownership? Share your comments below. And make sure to check PPT every Wednesday for a new women-friendly article. In the meantime, check out our guide on the Best EDC Items for Women or read up on why gun publications should be including women.

The post Female Firearms Ownership: Why Women Buy Guns appeared first on Pew Pew Tactical.

Pew Pew Tactical

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Buckeye Firearms Association

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U.S.A.– -(AmmoLand.com)- Doctor John Lott is the president and one of the principal researchers at the Crime Prevention Research Center. Dr. Lott recently reminded us that guns save lives and stop mass murder. I’d forgotten about a few of these incidents, though I’m sure I read a little about them at the time. In contrast, the news media covers mass murderers for days on end. To help offset that media bias, let’s look back only 10 months to see what we did.

You might have forgotten, but you saved lives.

• Do you remember the armed attack at a shooting range/ gun store in Metairie, Louisiana that happened only a few months ago? The murderer was carrying a loaded gun in his hands. The staff at the store asked him to put his gun away. Instead, the murderer attacked staff and customers. Two victims were killed before staff members and customers shot the murderer and ended the attack. Then, staff and customers called 911.
• It was back in August of 2020 when an armed man saved lives in a Walmart in Weslaco, Texas. Our armed good guy saw another man walk into the store dressed in black and carrying a rifle. The armed citizen drew his firearm and pointed it at the intruder. A security guard also helped hold the would-be attacker. The attacker was furious because you stopped him from killing people. Police arrived and took the rifle. The attacker was shot by law enforcement officers when he drew his handgun and threatened the police.
• You saved lives again last July in a sports bar in Dallas, Texas. A man was turned away from the bar due to restricted seating during the Covid epidemic. The angry customer came back and started shooting into the crowd. Four people were injured before armed patrons shot back and the attacker ran away. Police arrived minutes later.
• It was the middle of July when you were stopped at a traffic light in Brownsburg, Indiana. You saw two men run across the intersection. These two men were being chased by a man with a gun. The attacker shot them. You stepped out of your car and then the attacker shot at you. You shoot back and ended his attack. Emergency medical services are able to save one of the attacker’s intended victims.
• You saved lives in early July as you waited to get into a restaurant in Hummels Wharf, Pennsylvania. A stranger stopped his pickup truck in the middle of the parking lot. The driver got out and shot two people standing in line near. You draw your firearm and shoot back ending his attack. You call 911.

The list of armed defense incidents is much longer, but those are the ones that happened in the last 10 months. I suspect you are like me and forgot how often guns save lives. You forget the virtue of an armed society.

Give Dr. Lott a read.

The post Carry a Concealed Firearm Because You Can Stop Mass Murder and Save Lives appeared first on AmmoLand.com.

AmmoLand.com

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So your MySQL server has crashed.  What do you do now?  When a server is down, in my opinion, there are two steps that are essential and both are extremely important and neither should be neglected:

1. Save diagnostic information for determining the root cause analysis (RCA).
2. Get the server back up and running.

Too many people rush to Step #2 and lose pertinent diagnostics from Step #1.  Likewise, too many people will spend too much time on Step #1 and delay getting to Step #2 and restoring service.  The goal is to collect diagnostics as quickly as possible for later review while getting service restored as fast as possible.

As a Technical Account Manager (TAM) and assisting on server restoration calls, I have seen both issues at play.  Technical resources have a tendency to get so bogged down in trying to understand the cause of the server outage that they forget that the downtime is costing the business money.  The desire to crawl through server logs, review metrics, pour-over system metrics, and so on, can be too tempting for some who are concerned that important diagnostic data will be lost when service is restored.  This is a valid concern, but there must be a middle ground.

Conversely, many, especially those in management, will demand service is restored immediately to continue business functions.  Of course, after the service is back up, the demand for an RCA will come.  Sadly, many metrics, and some logs, are lost when a server is bounced.  Below are basic guidelines on what metrics to collect for MySQL.  The steps are in no particular order.

1. Save a copy of the MySQL Error Log.

   sudo cp /path/to/datadir/*.log /some/where/safe

2. Make a copy of the MySQL configuration file.

   sudo cp /path/to/my.cnf /some/where/safe

3. Make a copy of system logs and save them somewhere on persistent storage in a location that will not be overwritten.  Consider doing something like the following on Linux:

   sudo cp /var/log/syslog /some/where/safe/syslog
   sudo cp /var/log/messages /some/where/safe/messages
   sudo journalctl -e > /some/where/safe/journalctl.txt

4. If MySQL is running still and you can log in, get some MySQL metrics.  You will want to save the output into files somewhere.

   sudo mysqladmin -i10 -c10 proc > /some/where/safe/mysql_procs.txt
   mysql> SHOW GLOBAL VARIABLES;
   sudo mysqladmin -i10 -c10 ext > /some/where/safe/mysql_ext.txt
   mysql> SHOW ENGINE INNODB STATUS\G

5. If MySQL is running and you have Percona Toolkit, you should collect some pt-stalk output.

   sudo ./pt-stalk --no-stalk --iterations=2 --sleep=30 --dest=/some/where/safe -- --user=root --password=<mysql-root-pass>;

6. If you have space and time, a copy of the database files (data directory in MySQL) could be helpful.  Certainly, for many installations, getting all of the data files will be impossible.  If it is a small database and space and time allow, it can be best to get all the files just in case.

   sudo cp -R /path/to/datadir /some/where/safe/datadir

7. Copy database logs and save them somewhere safe for later review.  Systems like Percona XtraDB Cluster (PXC) will create GRA files during an issue which can be really helpful to look at to determine the root cause.  By combining the GRA header file with the contents of the GRA log files, you can use the mysqlbinlog command to get the records of transactions causing issues.  More information can be found in one of our older blogs here
   Percona XtraDB Cluster (PXC): what about GRA_*.log files?.

   sudo cp /path/to/data/dir/GRA* /some/where/safe/datadir/

8. Save system metrics pertaining to CPU, I/O, and memory usage:

   sudo mpstat -a 1 60 > /some/where/safe/mpstat.txt
   sudo vmstat 1 60 > /some/where/safe/vmstat.txt
   sudo iostat -dmx 1 60 > /some/where/safe/iostat.txt

9. Save system info.

   sudo cat /proc/cpuinfo > /some/where/safe/cpuinfo.txt

10. If you have Percona Toolkit, the following would be very helpful:

    sudo pt-summary > /some/where/safe/pt-summary.txt
    sudo pt-mysql-summary > /some/where/safe/pt-mysql-summary.txt

11. Get hardware diagnostics.

    # disk info
    sudo df -k > /some/where/safe/df_k.txt
    sudo lsblk -o KNAME,SCHED,SIZE,TYPE,ROTA > /some/where/safe/lsblk.txt
    sudo lsblk --all > $PTDEST/lsblk-all;
    
    # lv/pv/vg only for systems with LVM
    sudo lvdisplay --all --maps > /some/where/safe/lvdisplau-all-maps.txt
    sudo pvdisplay --maps > /some/where/safe/pvdisplay-maps.txt
    sudo pvs -v > /some/where/safe/pvs_v.txt
    sudo vgdisplay > /some/where/safe/vgdisplay.txt
    
    # nfsstat for systems with NFS mounts 
    sudo nfsstat -m > /some/where/safe/nfsstat_m.txt
    sudo nfsiostat 1 120 > /some/where/safe/nfsiostat.txt
    
    # Collect hardware information 
    sudo dmesg > /some/where/safe/dmesg.txt
    sudo dmesg -T free -m > /some/where/safe/dmesg_free.txt 
    sudo dmesg -T > /some/where/safe/dmesg_t.txt
    sudo ulimit -a > /some/where/safe/ulimit_a.txt
    sudo cat /proc/sys/vm/swappiness > /some/where/safe/swappiness 
    sudo numactl --hardware > /some/where/safe/numactl-hardware.txt

It goes without saying, it would be best to script the above into a useful bash script you can run when there is an issue.  Just be sure to test the script in advance of an issue.

Again, the goal is to preserve useful diagnostic data that could be useful for determining the root cause of the issue at a later time after the service is restored.  Just don’t get caught up in looking through the above diagnostics!  Certainly, more data is better but the above is a great starting point.  As time goes on, you may realize you wish you had other metrics and can add them to your script or Standard Operating Procedure (SOP).

Naturally, adding monitoring like Percona Monitoring and Management (PMM) would be a great option that can save you a lot of time and collect even more trends over time which can be extremely helpful.

With the above diagnostics, you would have a ton of information in the event of an issue to find the root cause.  Now, you can sort through the diagnostics.  Of course, if you need help with that, Percona can help you here as well.

Planet MySQL

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In ALTER TABLE for UUID we discuss currently proper way to store and handle UUID in MySQL. Currently it works, even in a performant way, but it still hurts. It should not.

Definition of UUID

The RFC 4122 defines various types of UUID, and how they are being formatted for presentation and as a bit field on the wire. As this document was written bei Leach and Salz, among others, RFC 4122 UUIDs are also called “Leach-Salz UUIDs” (for example in the Java Documentation).

There are other UUID variants, used in other systems (NCS, and Microsoft “backwards compatibility”).

A RFC 4122 UUID is a special 128 bit long value (“16 octets”). It is supposed to be laid out like this:

 0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| time_low |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| time_mid | time_hi_and_version |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|clk_seq_hi_res | clk_seq_low | node (0-1) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| node (2-5) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

The high bits in clk_seq_hi_res define the variant, and anything starting with the bit sequence 10 is a RFC 4122 compliant UUID.

The high nibble in time_hi_and_version defines the RFC 4122 Type (or version), the algorithm used. RFC 4122 itself defines versions 1 to 5 (version 0 is unused).

There is an expired draft that defines a version 6, which is specifically designed to use a primary key for databases. It uses the same timestamp value as Type 1, but stores the bytes so that ordering by creation time is preserved. It also relaxes the requirements on the node field, officially allowing different sources for bits than the MAC address. Sample implementations are available in various languages.

UUIDs are all over the place in Windows and also in Java. Databases have to handle them as “application generated primary keys”. That’s why they are important and should be treated with some attention.

Handling UUID in MySQL 8

MySQL provides functions to generate UUIDs, to check if a thing is a validly formatted string that looks like a UUID, and to convert UUIDs to 128 bit bitstrings and back.

The latter two functions have a special flag to improve performance with InnoDB. This flag is by default off. No attempt is made to automatically do the right thing dependent on the UUID type.

UUID function

The MySQL function UUID() returns a RFC 4122 Type 1 UUID.

mysql> select uuid_to_bin(uuid()) as uuid;
+------------------------------------+
| uuid                               |
+------------------------------------+
| 0x80462D3C96AB11EB94BBBA2278F258E1 |
+------------------------------------+
1 row in set (0.00 sec)

Formatted like in the RFC, we get the following values:

80462D3C
96AB 1 1EB
9 4 BB B A22
78F258E1

Specifically, the clk_seq_hi_res contains the variant value, 9, and the time_hi_and_version contains the version, 1.

According to the RFC, the variant 9 = 1001 = 10x (a RFC 4122 compliant UUID).

Of the Versions defined in RFC 4122, it is Version 1 or Type 1, “The time-based version in this document”. The generation algorithm is defined in section 4.2 of that RFC.

So a MySQL generated UUID is always a RFC 4122 Type 1 (time based) UUID.

Java generated UUID values

Compare with the Java UUID Class:

We have randomUUID(), returning a Type 4 UUID and nameUUIDFromBytes() for Type 3 and a generic Constructor that takes any 128 bit value. So what we get from Java is likely name based or random UUIDs generated by the application.

Name based UUIDs are fixed for a fixed name, so they pose no problem when used with MySQL as a primary key.

Random UUIDs are completely random. There is nothing to optimize for MySQL here.

Neither is a good choice to use as a kind of application controlled distribiuted primary key.

Based on the reasoning in ALTER TABLE for UUID, Java developers that are using UUID for this purpose would be well advised to implement and use a Type 1 UUID. It seems that such an implementation is not available by default as part of java.lang.util, but other implementations exist.

IS_UUID() function

The IS_UUID() predicate returns 1 for all strings that can be parsed as a UUID.

That is, it checks for one of three ways to write the UUID, and that it contains only valid hex digits in the places that actually contain data. No attempt is made to validate any of the bits. Code is here, and the actual parsing happens here.

UUID_TO_BIN() function

MySQL allows three ways to write UUIDs, as a 128 bit hex string (6ccd780cbaba102695645b8c656024db), as a 128 bit hex string with dashes in the right places (6CCD780C-BABA-1026-9564-5B8C656024DB) and as a 128 bit hex string with dashes in the right places and enclosed in curly braces ({6CCD780C-BABA-1026-9564-5B8C656024DB}).

This is not a particular dense packing of data for storage. The UUID_TO_BIN() function takes any of these strings and returns a VARBINARY(16) for storage.

The function has an optional second parameter, the swap_flag. When applied to a Type 1 UUID, the time bytes are being swapped around so that chronological ascending UUIDs from the same node are also having numerically ascending values. This optimizes storage with InnoDB.

• Type 1 UUID: It is recommended you define UUID columns as VARBINARY(16) and use theUUID_TO_BIN(uuid_string, 1) function to store data.
• Type 6 UUID: You should use UUID_TO_BIN(uuid_string, 0) to store Type 6 UUIDs, because Type 6 has been specifically created to avoid the swapping of time bytes around.
• Other types: These do not profit from swapping, so also use UUID_TO_BIN(uuid_string, 0).

BIN_TO_UUID function

The inverse function to UUID_TO_BIN is BIN_TO_UUID(). It needs the same swap_flag value as has been used at write time in order to unpack the data correctly.

It should hurt less

This all should hurt less.

• MySQL should have a native UUID column type, which stores data internally in a VARBINARY(16) (or BINARY(16)).
• It should accept all three notations as input (hex string, with dashes, with curly braces and dashes). It should return a hex string without dashes or curlies.
• It should validate variant and type (version), allowing Types 1 to 6.
• It should auto-convert (swap) data for Type 1, but not for any other type.
• There should be a formatting function that turns a hex string without dashes into a UUID string with dashes, or a UUID string with dashes and curlies.

That is, I want to be able to

mysql> create table u ( u uuid not null primary key, dummy integer );
mysql> insert into u values (uuid(), 1);
mysql> select u from u\G
u: 6ccd780cbaba102695645b8c656024db
mysql> select format_uuid(u, 0) as u from u\G
u: 6CCD780C-BABA-1026-9564-5B8C656024DB
mysql> select format_uuid(u) as u from u\G
u: 6CCD780C-BABA-1026-9564-5B8C656024DB
mysql> select format_uuid(u, 1) as u from u\G
u: {6CCD780C-BABA-1026-9564-5B8C656024DB}

and internally, this is stored as 0x1026BABA6CCD780C95645B8C656024DB, because variant is RFC 4122 and Type is 1.

For any other Type of the RFC 4122 the internal swapping does not happen.

Trying to store anything that is not a RFC 4122 variant is an error. Trying to store anything that is a RFC 4122 variant but not a Type 1 to 6 is an error.

Planet MySQL