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How do C++ class members get initialized if I don't do it explicitly?
...ssion-list is how the member is constructed. For example, in
static const char s_str[] = "bodacydo";
class Example
{
private:
int *ptr;
string name;
string *pname;
string &rname;
const string &crname;
int age;
public:
Example()
: name(s_str, s_str + 8), ...
pandas GroupBy columns with NaN (missing) values
...s far result in potentially dangerous behavior as it is quite possible you select a dummy value that is actually part of the dataset. This is increasingly likely as you create groups with many attributes. Simply put, the approach doesn't always generalize well.
A less hacky solve is to use pd.drop_...
Count, size, length…too many choices in Ruby?
...e will generate a query that requests all of the items from the database ('select * from mytable') and then give you the number of items resulting, whereas .count will generate a single query ('select count(*) from mytable') which is considerably faster.
Because these ORMs are so prevalent I follow...
How to query MongoDB with “like”?
...d all entries for name? or the wildcard for * in SQL? Something that does select name from users; which just lists all the users?
– anon58192932
Oct 18 '17 at 19:15
1
...
Changing navigation bar color in Swift
...UIColor.whiteColor()
UINavigationBar.appearance().barTintColor = Style.SELECTED_COLOR
UINavigationBar.appearance().translucent = false
UINavigationBar.appearance().clipsToBounds = false
UINavigationBar.appearance().backgroundColor = Style.SELECTED_COLOR
UINavigationBar.appearance...
What is the relative performance difference of if/else versus switch statement in Java?
... just ints. From the Java Tutorials: "A switch works with the byte, short, char, and int primitive data types. It also works with enumerated types (discussed in Enum Types), the String class, and a few special classes that wrap certain primitive types: Character, Byte, Short, and Integer (discussed ...
Faster way to develop and test print stylesheets (avoid print preview every time)?
...P (Mac) or Ctrl+Shift+P (Windows, Linux))
2. Start typing Rendering and select Show Rendering.
3. For the Emulate CSS Media dropdown, select print.
UPDATE 29/02/2016
The DevTools docs have moved and the above link provides inaccurate information. The updated docs regarding Media type em...
Why do you create a View in a database?
...e a View in their database? Why not just run a normal stored procedure or select?
25 Answers
...
Disable validation of HTML5 form elements
...ecause it should absolutely work without JavaScript.
In my case, I put a select element with 2 options (http:// or https://) before the URL input because I just need websites (and no ftp:// or other things). This way I avoid typing this weird prefix (the biggest regret of Tim Berners-Lee and maybe...
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...