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Efficiently convert rows to columns in sql server
... for ColumnName in (' + @cols + N')
) p '
exec sp_executesql @query;
See Demo.
Using an aggregate function
If you do not want to use the PIVOT function, then you can use an aggregate function with a CASE expression:
select
max(case when columnname = 'FirstName' then ...
What does Ruby have that Python doesn't, and vice versa?
...ound as an object, and overwrite it:
def func(): print "hello"
def another_func(f): f()
another_func(func)
def func2(): print "goodbye"
func = func2
This is a fundamental feature of modern scripting languages. JavaScript and Lua do this, too. Ruby doesn't treat functions this way; naming a fun...
Apache not starting on MAMP Pro
.... Go to bin -> apache2 -> bin.
Then rename the file from envvars to _envvars.
I also came across another problem of it not working correctly. Make sure the ports are Apache defaults, NOT MAMP defaults (port 80 etc). If it works straight away, this should not apply to you.
...
HAXM 安装/启动失败？ - App Inventor 2 离线版 - 清泛IT社区，为创新赋能！
报错如下：
emulator: Android emulator version 30.3.5.0 (build_id 7033400) (CL:N/A)
127.0.0.1 - - [01/Apr/2025 16:55:37] "GET /echeck/ HTTP/1.1" 200 39
handleCpuAcceleration: feature check for hvf
emulator: ERROR: x86_64 emulation currently requires hardware acceleration!
CPU accel...
Why use sprintf function in PHP?
... get the rightly aligned 8 digit and commas separated integer. Using number_format is less convenient in a printf style.
– e2-e4
Nov 16 '10 at 6:41
...
get size of json object
... check the size i.e. like that:
var data = {one : 1, two : 2, three : 3};
_.size(data);
//=> 3
_.keys(data);
//=> ["one", "two", "three"]
_.keys(data).length;
//=> 3
share
|
improve this ...
How do I move files in node.js?
...e rename function to do that.
http://nodejs.org/docs/latest/api/fs.html#fs_fs_rename_oldpath_newpath_callback
fs.rename(oldPath, newPath, callback)
Added in: v0.0.2
oldPath <String> | <Buffer>
newPath <String> | <Buffer>
callback <Function>
Asynchronous...
What is mattr_accessor in a Rails module?
... couldn't really find this in Rails documentation but it seems like 'mattr_accessor' is the Module corollary for 'attr_accessor' (getter & setter) in a normal Ruby class .
...
Pandas every nth row
...simpler solution to the accepted answer that involves directly invoking df.__getitem__.
df = pd.DataFrame('x', index=range(5), columns=list('abc'))
df
a b c
0 x x x
1 x x x
2 x x x
3 x x x
4 x x x
For example, to get every 2 rows, you can do
df[::2]
a b c
0 x x x
...
Custom thread pool in Java 8 parallel stream
...gt;
// Parallel task here, for example
IntStream.range(1, 1_000_000).parallel()
.filter(PrimesPrint::isPrime)
.boxed().collect(Collectors.toList())
).get();
System.out.println(primes);
} catch (InterruptedException | ExecutionException e) {
...