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Update or Insert (multiple rows and columns) from subquery in PostgreSQL
...table.col1 = 123;
For the INSERT
Use:
INSERT INTO table1 (col1, col2)
SELECT col1, col2
FROM othertable
You don't need the VALUES syntax if you are using a SELECT to populate the INSERT values.
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How to pull a random record using Django's ORM?
...on't know about other databases).
order_by('?')[:N] will be translated to SELECT ... FROM ... WHERE ... ORDER BY RAND() LIMIT N query.
It means that for every row in table the RAND() function will be executed, then the whole table will be sorted according to value of this function and then first N...
How to remove a Gitlab project?
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Go to the project page
Select "Settings"
Select the "General" section (you must be in the repository you want to delete to delete it)
If you have enough rights, then at the bottom of the page will be a button for "Advanced settings" (i.e. project s...
How to get element by innerText
... This should be the top answer. XPath can do much more, like select node by attribute value, select node sets ... Simple intro: w3schools.com/xml/xpath_syntax.asp
– Timathon
Dec 2 '17 at 2:43
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Change C++/CLI project to another framework than 4.0 with vs2010
... the Platform Toolset setting in the General property page. You must then select "v90" to get a proper build that targets 3.5. It is however clumsy, you must have all intermediate versions of VS installed on the machine to have that selection available.
Why you need VS2008 installed requires an e...
OrderBy descending in Lambda expression?
... orderby person.Name descending, person.Age descending
select person.Name;
is equivalent to:
var query = people.OrderByDescending(person => person.Name)
.ThenByDescending(person => person.Age)
.Select(person => person.Name);
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Quicksort: Choosing the pivot
...states "Hoare suggested partitioning around the median of several randomly selected lines. Sedgewick [...] recommended choosing the median of the first [...] last [...] and middle". This indicates that both techniques for 'median-of-three' are known in the literature. (Update 2014-11-23: The articl...
How to find event listeners on a DOM node when debugging or from the JavaScript code?
I have a page where some event listeners are attached to input boxes and select boxes. Is there a way to find out which event listeners are observing a particular DOM node and for what event?
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Emacs bulk indent for Python
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I use the following snippet. On tab when the selection is inactive, it indents the current line (as it normally does); when the selection is inactive, it indents the whole region to the right.
(defun my-python-tab-command (&optional _)
"If the region is active, s...
How to get the system uptime in Windows? [closed]
...can also click CTRL+SHIFT+ESC to get to the Task Manager.
In Task Manager, select the Performance tab.
The current system uptime is shown under System or Performance ⇒ CPU for Win 8/10.
2: By using the System Information Utility
The systeminfo command line utility checks and displays various ...