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Difference between CTE and SubQuery?
...rsions, they are probably very similar. You would have to use the profiler and actual execution plan to spot any differences, and that would be specific to your setup (so we can't tell you the answer in full).
In general; A CTE can be used recursively; a sub-query cannot. This makes them especially...
Generating a unique machine id
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Parse the SMBIOS yourself and hash it to an arbitrary length. See the PDF specification for all SMBIOS structures available.
To query the SMBIOS info from Windows you could use EnumSystemFirmwareEntries, EnumSystemFirmwareTables and GetSystemFirmware...
Why do you need to put #!/bin/bash at the beginning of a script file?
I have made Bash scripts before and they all ran fine without #!/bin/bash at the beginning.
9 Answers
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How do I see active SQL Server connections?
...L Server 2008 Enterprise. I want to see any active SQL Server connections, and the related information of all the connections, like from which IP address, connect to which database or something.
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How to detect when WIFI Connection has been established in Android?
...that a valid network connection for HTTP exists. What should I listen for and what additional tests do I need to make to know that a valid connection exists.
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How to use Namespaces in Swift?
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The link to the Apple dev forums is now broken, and Apple has not imported that thread into the new forums.developer.apple.com forums site, unfortunately.
– Dai
Feb 15 '17 at 2:07
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How to submit a form using PhantomJS
... tool btw!) to submit a form for a page that I have login credentials for, and then output the content of the destination page to stdout. I'm able to access the form and set its values successfully using phantom, but I'm not quite sure what the right syntax is to submit the form and output the conte...
What is the difference between `git fetch origin` and `git remote update origin`?
...no difference when used like this.
remote update is a very high-level command - it supports grouped remotes (remotes.<group> = <list>), and updating all remotes (except those with remote.<name>.skipDefaultUpdate set), but not any of the more specific options of fetch. Under the ho...
HTML Form: Select-Option vs Datalist-Option
I was wondering what the differences are between Select-Option and Datalist-Option. Is there any situation in which it would be better to use one or the other? An example of each follows:
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Update one MySQL table with values from another
...ue = original.value)
SET tobeupdated.id = original.id
That should do it, and really its doing exactly what yours is. However, I prefer 'JOIN' syntax for joins rather than multiple 'WHERE' conditions, I think its easier to read
As for running slow, how large are the tables? You should have indexes...