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How to pad zeroes to a string?
...)) # or
print('{0:05d}'.format(number)) # or (explicit 0th positional arg. selection)
print('{n:05d}'.format(n=number)) # or (explicit `n` keyword arg. selection)
print(format(number, '05d'))
Documentation for string formatting and f-strings.
...
Visual Studio move project to a different folder
...olution in VS2012
Move your project to the new location
Open your solution
Select the project that failed to load
In the Properties tool window, there an editable “File path” entry that allows you to select the new project location
Set the new path
Right click on the project and click reload
...
Difference between string and text in rails?
... load varchar in one go, but store text (and blob) outside of the table. A SELECT name, amount FROM products could, be a lot slower when using text for name than when you use varchar. And since Rails, by default loads records with SELECT * FROM... your text-columns will be loaded. This will probably...
?? Coalesce for empty string?
...u call this Coalesce when it doesn't bring the values together, but merely selects the one that isn't empty? It's a confusing name dude.
– Jimmyt1988
Jan 10 '17 at 11:40
8
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Local file access with JavaScript
...
If the user selects a file via <input type="file">, you can read and process that file using the File API.
Reading or writing arbitrary files is not allowed by design. It's a violation of the sandbox. From Wikipedia -> Javascri...
Maven: Command to update repository after adding dependency to POM
...:
Right click on the project ->Run As -- >Run configurations.
Then select mavenBuild.
Then click new button to create a configuration of the selected
type .Click on Browse workspace then select your project and in
goals specify eclipse:eclipse
You can refer to how to run the command mvn e...
Group by with multiple columns using lambda
....Key.Country == "Ireland" && a.Key.Gender == "M")
.SelectMany(a => a)
.ToList();
Where CustomerGroupingKey takes the group keys:
private class CustomerGroupingKey
{
public CustomerGroupingKey(string country, string gender)
{
...
How to get the pure text without HTML element using JavaScript?
...n many ways. innerText tries to approximate what would happen if you would select what you see (rendered html) and copy it to the clipboard, while textContent sort of just strips the html tags and gives you what's left.
innerText also has compatability with old IE browsers (came from there).
...
How to read a large file - line by line?
... efficient ways in ranked order (first is best) -
use of with - supported from python 2.5 and above
use of yield if you really want to have control over how much to read
1. use of with
with is the nice and efficient pythonic way to read large files. advantages - 1) file object is automatically clo...
Query a parameter (postgresql.conf setting) like “max_connections”
... SHOW, such as minimum
and maximum values.
For your original request:
SELECT *
FROM pg_settings
WHERE name = 'max_connections';
Finally, there is current_setting(), which can be nested in DML statements:
SELECT current_setting('max_connections');
Related:
How to test my ad-hoc SQL wit...