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Can I concatenate multiple MySQL rows into one field?
...d in their comment, you can also sort the values before imploding it using ORDER BY:
SELECT person_id, GROUP_CONCAT(hobbies ORDER BY hobbies ASC SEPARATOR ', ')
FROM peoples_hobbies
GROUP BY person_id;
As Dag stated in his comment, there is a 1024 byte limit on the result. To solve this, run this q...
What is the difference between a “function” and a “procedure”?
... based on input.
A procedure is a set of command which can be executed in order.
In most programming languages, even functions can have a set of commands. Hence the difference is only in the returning a value part.
But if you like to keep a function clean, (just look at functional languages), yo...
Why does C++ rand() seem to generate only numbers of the same order of magnitude?
...
If you want different orders of magnitude, why not simply try pow(2, rand())? Or perhaps choose the order directly as rand(), as Harold suggested?
share
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How to print (using cout) a number in binary form?
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#include <iostream>
#include <cmath> // in order to use pow() function
using namespace std;
string show_binary(unsigned int u, int num_of_bits);
int main()
{
cout << show_binary(128, 8) << endl; // should print 10000000
cout << show_binar...
Changing Vim indentation behavior by file type
...ds per filetype(s) this way, and they are guaranteed to be executed in the order given.
– underscore_d
Oct 20 '15 at 16:13
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show 1 more com...
Java : How to determine the correct charset encoding of a stream
...y in an UTF-8 format and does it include a BOM (en.wikipedia.org/wiki/Byte_order_mark)?
– Benny Neugebauer
Sep 12 '16 at 11:53
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How to get JSON response from http.Get
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You need upper case property names in your structs in order to be used by the json packages.
Upper case property names are exported properties. Lower case property names are not exported.
You also need to pass the your data object by reference (&data).
package main
impo...
Remote debugging Tomcat with Eclipse
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THis will not work in Tomcat 8. In order for it to work in Tomcat 8, you have to leave out step 1.
– Dave
Jul 3 '15 at 20:13
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How to change the order of DataFrame columns?
... + cols[:-1]
In [13]: cols
Out[13]: ['mean', 0L, 1L, 2L, 3L, 4L]
Then reorder the dataframe like this:
In [16]: df = df[cols] # OR df = df.ix[:, cols]
In [17]: df
Out[17]:
mean 0 1 2 3 4
0 0.445543 0.445598 0.173835 0.343415 0.682252 ...
What does “javascript:void(0)” mean?
... is a non-JavaScript way of doing the same thing (for example, ‘thispage.php?show=foo’ that sets foo visible to begin with), you can link to that.
Otherwise, if a link points only to some script, it is not really a link and should not be marked up as such. The usual approach would be to add the...