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Computed / calculated / virtual / derived columns in PostgreSQL
...y as column?
The expression (looking like a column) is not included in a SELECT * FROM tbl, though. You always have to list it explicitly.
Can also be supported with a matching expression index - provided the function is IMMUTABLE. Like:
CREATE FUNCTION col(tbl) ... AS ... -- your computed expr...
Setting Vim whitespace preferences by filetype
...local ts=4 sw=4 sts=0 noexpandtab
Also note:
You can make vim show tab characters by using :set list.
Once you have the tab/space options set correctly, you can make vim repair the file (replace spaces with tabs or vice versa) using the :retab! command.
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Using IntelliJ to amend git commit message
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Amend is supported: invoke "Commit Changes" and select the checkbox "Amend commit" in the Commit Dialog. Then press "Commit" button, and the commit will be amended to the previous one.
However, the support is limited:
you can't see the details of the commit being amend...
Select elements by attribute in CSS
Is it possible to select elements in CSS by their HTML5 data attributes (for example, data-role )?
5 Answers
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Naming of ID columns in database tables
...!)and forget to change the alias in the join condition.
So you now have
select t1.field1, t2.field2, t3.field3
from table1 t1
join table2 t2 on t1.id = t2.table1id
join table3 t3 on t1.id = t3.table2id
when you meant
select t1.field1, t2.field2, t3.field3
from table1 t1
join table2 t2 on t1...
Getting Checkbox Value in ASP.NET MVC 4
... the value on the checkbox element to false. This means that when you then select the checkbox, you are posting the value "false" with the form. When you don't select it, it doesn't get posted, so the model defaults to false. Which is why you are seeing a false value in both cases.
The value is onl...
Login failed for user 'IIS APPPOOL\ASP.NET v4.0'
....
In SSMS, under the server, expand Security, then right click Logins and select "New Login...".
In the New Login dialog, enter the app pool as the login name and click "OK".
You can then right click the login for the app pool, select Properties and select "User Mapping". Check the appropriate...
How to select an element inside “this” in jQuery?
I know can I select an element this way:
2 Answers
2
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EOL conversion in notepad ++
...That functionality is already built into Notepad++. From the "Edit" menu, select "EOL Conversion" -> "UNIX/OSX Format".
screenshot of the option for even quicker finding (or different language versions)
You can also set the default EOL in notepad++ via "Settings" -> "Preferences" -> "New...
Which machine learning classifier to choose, in general? [closed]
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Model selection using cross validation may be what you need.
Cross validation
What you do is simply to split your dataset into k non-overlapping subsets (folds), train a model using k-1 folds and predict its performance using the...