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How to get error message when ifstream open fails
... another system call triggers an error between the execution of the f.open and use of errno.
On system with POSIX standard:
errno is thread-local; setting it in one thread does not affect its
value in any other thread.
Edit (thanks to Arne Mertz and other people in the comments):
e.wha...
How to find all tables that have foreign keys that reference particular table.column and have values
...ma;
SELECT *
FROM
KEY_COLUMN_USAGE
WHERE
REFERENCED_TABLE_NAME = 'X'
AND REFERENCED_COLUMN_NAME = 'X_id';
If you have multiple databases with similar tables/column names you may also wish to limit your query to a particular database:
SELECT *
FROM
KEY_COLUMN_USAGE
WHERE
REFERENCED_TABLE...
Difference between $(this) and event.target?
I'm new to jQuery, and was making tabbed panels, following the tutorial in JavaScript and jQuery : The Missing Manual , there's that first line when the author does this :
...
How can I get Knockout JS to data-bind on keypress instead of lost-focus?
This example of knockout js works so when you edit a field and press TAB, the viewmodel data and hence the text below the fields is updated.
...
Find a Git branch containing changes to a given file
...file in one of them, but I'm not sure which one. Is there some kind of command I can run to find which branches contain changes to a certain file?
...
Rotating x axis labels in R for barplot
...I'm guessing there's an easier way. But you could suppress the bar labels and the plot text of the labels by saving the bar positions from barplot and do a little tweaking up and down. Here's an example with the mtcars data set:
x <- barplot(table(mtcars$cyl), xaxt="n")
labs <- paste(names(...
SELECT DISTINCT on one column
....WHERE SKU LIKE 'FOO%') a WHERE a.RowNumber = 1
– Andre Nel
Jun 21 '17 at 11:46
This works although it's not a CTE ...
Is it Pythonic to use list comprehensions for just side effects?
...
It is very anti-Pythonic to do so, and any seasoned Pythonista will give you hell over it. The intermediate list is thrown away after it is created, and it could potentially be very, very large, and therefore expensive to create.
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Is there a way to perform “if” in python's lambda
...eason to use a lambda, period. Assigning a lambda to a variable -- as a stand-in for def -- is generally a Very Bad Idea (tm). Just use a def so mere mortal programmers can read, interpret, understand and maintain it.
– S.Lott
Oct 18 '09 at 22:15
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Secondary axis with twinx(): how to add to legend?
... a plot with two y-axes, using twinx() . I also give labels to the lines, and want to show them with legend() , but I only succeed to get the labels of one axis in the legend:
...