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Usages of Null / Nothing / Unit in Scala
...wered Apr 23 '13 at 16:40
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...
Postgresql aggregate array
...
Use array_agg: http://www.sqlfiddle.com/#!1/5099e/1
SELECT s.name, array_agg(g.Mark) as marks
FROM student s
LEFT JOIN Grade g ON g.Student_id = s.Id
GROUP BY s.Id
By the way, if you are using Postgres 9.1, you don't need ...
Why would I use Scala/Lift over Java/Spring? [closed]
... of a REST request:
serve {
case "api" :: "user" :: AsUser(user) :: _ XmlGet _ => <b>{user.name}</b>
case "api" :: "user" :: AsUser(user) :: _ JsonGet _ => JStr(user.name)
}
Using Scala's built-in pattern matching, we match an incoming request, extract the third part...
When to use symbols instead of strings in Ruby?
...eference the symbol, saving memory. So every time the interpreter reads :my_key it can take it from memory instead of instantiate it again. This is less expensive than initializing a new string every time.
You can get a list all symbols that are already instantiated with the command Symbol.all_sym...
Displaying the build date
...Info target = null)
{
var filePath = assembly.Location;
const int c_PeHeaderOffset = 60;
const int c_LinkerTimestampOffset = 8;
var buffer = new byte[2048];
using (var stream = new FileStream(filePath, FileMode.Open, FileAccess.Read))
stream.Read(buffer, 0, 2048);
...
java.sql.SQLException: Incorrect string value: '\xF0\x9F\x91\xBD\xF0\x9F…'
...se 4-byte UTF8 with Connector/J configure the MySQL server with
character_set_server=utf8mb4. Connector/J will then use that setting
as long as characterEncoding has not been set in the connection
string. This is equivalent to autodetection of the character set.
Adjust your columns and datab...
How can I use an array of function pointers?
...ointers.
void fun1()
{
}
void fun2()
{
}
void fun3()
{
}
void (*func_ptr[3])() = {fun1, fun2, fun3};
main()
{
int option;
printf("\nEnter function number you want");
printf("\nYou should not enter other than 0 , 1, 2"); /* because we have only 3 functions */
scanf("%d",&...
Instance variables vs. class variables in Python
...test:
import timeit
setup='''
XGLOBAL= 5
class A:
xclass = 5
def __init__(self):
self.xinstance = 5
def f1(self):
xlocal = 5
x = self.xinstance
def f2(self):
xlocal = 5
x = A.xclass
def f3(self):
xlocal = 5
x = XGLOBAL
...
Should one call .close() on HttpServletResponse.getOutputStream()/.getWriter()?
...f it not closed.
public void close() throws IOException
{
if (_closed)
return;
if (!isIncluding() && !_generator.isCommitted())
commitResponse(HttpGenerator.LAST);
else
flushResponse();
super.close();
}
Also as ...
Make a URL-encoded POST request using `http.NewRequest(…)`
...alues{}
data.Set("name", "foo")
data.Set("surname", "bar")
u, _ := url.ParseRequestURI(apiUrl)
u.Path = resource
urlStr := u.String() // "https://api.com/user/"
client := &http.Client{}
r, _ := http.NewRequest(http.MethodPost, urlStr, strings.NewReader(data.Encode()...