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I had an evil idea so I ran this script on my local SQL server database:
CREATE PROCEDURE TESTPROC
AS BEGIN
SELECT 1
EXEC TESTPROC
END
When I executed the stored procedure, it stopped after 32 levels of nesting. My evil plan failed and I learnt something new today.
"It is easy to decipher extraterrestrial signals after deciphering Javascript and VB6 themselves.", ISanti[ ^]
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If you change to a recursive CTE you can play around with OPTION (MAXRECURSION 100)
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Each time a stored procedure calls another stored procedure or executes managed code by referencing a common language runtime (CLR) routine, type, or aggregate, the nesting level is incremented. When the maximum of 32 is exceeded, the transaction is terminated.
"These people looked deep within my soul and assigned me a number based on the order in which I joined."
- Homer
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I will take over the world before you do.
Just letting you know! 
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No it won't, unless it takes over 32 people at a time. 
"It is easy to decipher extraterrestrial signals after deciphering Javascript and VB6 themselves.", ISanti[ ^]
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It will take over thousands upon thousands!
And it's only 10 years away around the corner!!!! 
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I saw something similar happen with a trigger making a change that was then running the same trigger again.
The updates were extremely slow and I discovered that there was, like you have discovered, a point at which SQL Server gave up - when the recursion was 32 deep.
You would hope that the SQL Server would just catch this sort of thing at compile time.
“That which can be asserted without evidence, can be dismissed without evidence.”
― Christopher Hitchens
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I resorted to a GOTO in an SQL query Loop that created a new transaction to work round a repetitive action with an unknown data set size. It was dirty, but worked. Glad I didn't try recursion as that would have definitely ended in tears by the sound of things!
You can read about the problem here.....Developing Automated Data Purge Solution, but it basically looks like this;
LoopStart:
IF (@Count - @RowCountTotal) > @BatchSize
Begin
Begin Transaction
Delete Top (@BatchSize) From Comment Where CommentTime < @StartDate
Set @RowCountTotal = @RowCountTotal + @@RowCount
Commit Transaction
Goto LoopStart
End
Else
If (@Count - @RowCountTotal) > 0
Begin<br />
Begin Transaction
Delete Top (@Count - @RowCountTotal) From Comment Where CommentTime < @StartDate
Set @RowCountTotal = @RowCountTotal + @@RowCount<br />
Commit Transaction
End
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IMO, recursion is inherently dangerous, and must be avoided whenever possible. Moreover, when you must use recursion, you must also take steps to ensure that your recursive routine converges and unwinds its recursive stack. Every recursive routine must incorporate a test that stops the recursion in such a way that the recursion depth is self-limiting.
This is true regardless of the programming language in which the recursion occurs. Whenever I encounter a recursion, my first thought is to investigate other algorithms that don't rely on recursion. More often than not, I have managed to succeed in finding one.
David A. Gray
Delivering Solutions for the Ages, One Problem at a Time
Interpreting the Fundamental Principle of Tabular Reporting
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I have conclusive proof of something that I have long suspected; file times for files that fall outside the current DST/Standard time period are reported off by 1 hour by the Windows command prompt (CMD.exe). I'll be publishing the proof later today.
David A. Gray
Delivering Solutions for the Ages, One Problem at a Time
Interpreting the Fundamental Principle of Tabular Reporting
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Thanks for the article citation. Nevertheless, since Windows has the transition date tables mentioned in the article, and NTFS stores UTC times on disk, I see no reason that it shouldn't be fixed, even if doing so required a new switch. After all, said switch could be set in the DIRCMD environment variable.
David A. Gray
Delivering Solutions for the Ages, One Problem at a Time
Interpreting the Fundamental Principle of Tabular Reporting
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Like the Unix linefeed mode support in Notepad that will be introduced after 30 years with the next Windows 10 version?
That will be enabled by default but can be disabled with a registry key.
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Keep in mind that MS just finally "discovered" Linux. 
David A. Gray
Delivering Solutions for the Ages, One Problem at a Time
Interpreting the Fundamental Principle of Tabular Reporting
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Hmmmm,
Looking forward to you discovering File System Tunneling[^]. Report back and let us know what you've discovered.
Start your research here[^].
Best Wishes,
-David Delaune
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Quarks, eh?
I didn't respond in the thread yesterday because I was using my phone to access my email, since the fiber cable to my house was down, due to a break in the last segment of the line. However, I managed to follow the link and read both articles, which were most intriguing.
Eventually, I'll probably delve into it more. Meanwhile, I've run some tests in assorted scripting languages, with mixed results. So far, I've tested the stat() function, as implemented in Perl and PHP. Next come JavaScript, in the Node CLI, and VBScript, and, finally, PowerShell, which I anticipate will mirror the C# program that put the nail in the coffin. Now that I've learned all this, I think the resulting article will be a third installment in the Time Zone Lab series that I started a couple of years ago.
David A. Gray
Delivering Solutions for the Ages, One Problem at a Time
Interpreting the Fundamental Principle of Tabular Reporting
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David A. Gray wrote: So far, I've tested the stat() function, as implemented in Perl and PHP. Next come JavaScript, in the Node CLI, and VBScript, and, finally, PowerShell, which I anticipate will mirror the C# program that put the nail in the coffin. Now that I've learned all this, I think the resulting article will be a third installment in the Time Zone Lab series that I started a couple of years ago.
I expect that you will get the same results from Perl, PHP, Javascript, VBScript because all of those high-level languages will call into the GetFileAttributesEx Windows API to get file time stamps.
The C lib function _stat() and all 32 bit variants are forwarded to GetFileAttributes
The C lib function _stat64() and all 64 bit variants functions are forwarded to GetFileAttributesEx.
GetFileAttributes simply forwards to GetFileAttributesEx
Finally... GetFileAttributeEx calls into the NtQueryAttributesFile function[^] via a SYSCALL and then in kernelmode the request walks it's way through the filter drivers down to the filesystem driver.
You are basically testing NtQueryAttributesFile function multiple times from the Thirteenth Floor.
Those high level languages may format the date differently... but they are all getting the same timestamp from the filesystem layer.
Best Wishes,
-David Delaune
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The problem with that theory, which has already born fruit, is that all of those functions retrieve a UTC time stamp. The issue is what happens on the 12th floor when the runtime that got the ball rolling converts the returned time stamp to local time. The outcome depends on whether they take into account the actual date and the DST transition dates on either side of it. Some frameworks take the same dumb approach implemented by CMD.exe, which treats all times as if they were in the current transition (DST vs. Standard Time). So far, I've already found two other frameworks (Perl and VBScript) that take that naieve approach.
David A. Gray
Delivering Solutions for the Ages, One Problem at a Time
Interpreting the Fundamental Principle of Tabular Reporting
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Hi,
There use to be some amazing articles on the internet back in the 1990's that had charts and listed all the differences between the programming languages and how the handle date/time conversions. I briefly searched but could not find those old articles. Even Dr. Dobbs[^] has retired.
I think it's a great idea to write an article about those differences. Looking forward to reading what you come up with.
Best Wishes,
-David Delaune
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How does PowerShell compare?
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I haven't gotten to PowerShell, per se. However, since it runs atop the .NET Framework, I expect it to exhibit the same (correct) behavior as my test program. Hence, between that and the fact that I seldom use PowerShell, I wasn't planning a separate evaluation of it.
David A. Gray
Delivering Solutions for the Ages, One Problem at a Time
Interpreting the Fundamental Principle of Tabular Reporting
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even though I used their supported restart options. I'm not sure yet, but I think that MS has coded up a "reboot it anyway" feature.
Just curious if you Windows 10 users out there have managed to find away to stop this elephanting reboot crap.
Right now, you would not want me near the nuclear football... I have some targets in mind.
Charlie Gilley
<italic>Stuck in a dysfunctional matrix from which I must escape...
"Where liberty dwells, there is my country." B. Franklin, 1783
“They who can give up essential liberty to obtain a little temporary safety deserve neither liberty nor safety.” BF, 1759
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Um, certain updates that Microsoft makes to Windows, etc. require a reboot whether you like it or not. The alternative is to not use Windows. It really is not a big deal.
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Slacker007 wrote: s. It really is not a big deal.
Just wait until your phone does this.
Or your car.
Oh wait no worries M$ doesn't have a phone.
Why any software company would think restarting any device at their convenience would be best for any user is beyond understanding. 
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It's past any sort of understanding. Windows 7 was rock solid for me, unless I got too happy with USB devices. Other than that, I might have had one blue screen per year. Windows 10 does two things that boggle the mind:
- the reboot issue. What the hell, lets just put in a bug to blue screen it.
- driver updates: this is a killer for laptop users.
I don't know what is wrong with Microsoft. They are tripling down on this foolishness. I'm already doing an audit on the s/w I use, looking for Linux based solutions (I live in the embedded world, so I might be able to do this). For the times I cannot avoid using MS, I'll put it in a VM.
Charlie Gilley
<italic>Stuck in a dysfunctional matrix from which I must escape...
"Where liberty dwells, there is my country." B. Franklin, 1783
“They who can give up essential liberty to obtain a little temporary safety deserve neither liberty nor safety.” BF, 1759
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