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How to assign Profile values?
...sn't use profiles. This code is probably not fast enough for a site with 1,000,000 page views a day. I was working on another project when I wrote this.
– Joel Spolsky♦
Dec 3 '09 at 3:55
...
Java Equivalent of C# async/await?
...usFileChannel.open(path);
ByteBuffer buffer = ByteBuffer.allocate(100_000);
await channel.read(buffer, 0, buffer, this);
return buffer.get(0);
}
Then I would imagine the compiler will transform the original async/await code into something like this:
public static Future<Byte> r...
Which are more performant, CTE or temporary tables?
...cs.
Test Data
CREATE TABLE T(A INT IDENTITY PRIMARY KEY, B INT , F CHAR(8000) NULL);
INSERT INTO T(B)
SELECT TOP (1000000) 0 + CAST(NEWID() AS BINARY(4))
FROM master..spt_values v1,
master..spt_values v2;
Example 1
WITH CTE1 AS
(
SELECT A,
ABS(B) AS Abs_B,
F
FROM T
)
SELECT...
static linking only some libraries
...cpp
# c++ test.cpp /usr/lib/libX11.a
# ldd a.out
linux-vdso.so.1 => (0x00007fff385cc000)
libstdc++.so.6 => /usr/lib/libstdc++.so.6 (0x00007f9a5b233000)
libm.so.6 => /lib/libm.so.6 (0x00007f9a5afb0000)
libgcc_s.so.1 => /lib/libgcc_s.so.1 (0x00007f9a5ad99000)
libc.so.6 => /lib/libc.so....
Are loops really faster in reverse?
...j=i+1, i=j.]]
Really fast loops can be done by unrolling them:
for(i=800000;i>0;--i)
do_it(i);
It can be way slower than
for(i=800000;i>0;i-=8)
{
do_it(i); do_it(i-1); do_it(i-2); ... do_it(i-7);
}
but the reasons for this can be quite complicated (just to mention, there are ...
How to parse XML in Bash?
...m-apple-iso@2x.png</Key>
<LastModified>2011-07-25T22:23:04.000Z</LastModified>
<ETag>&quot;0032a28286680abee71aed5d059c6a09&quot;</ETag>
<Size>1785</Size>
<StorageClass>STANDARD</StorageClass>
</Contents>
</List...
SQL Server : Columns to Rows
...me that xml is about 2.5 times slower that dynamic (it was one query on ~250000 rows table, so this estimate is no way exact). You could compare it yourself if you want, here's sqlfiddle example, on 100000 rows it was 29s (xml) vs 14s (dynamic);
may be it could be harder to understand for people not...
Check if a Postgres JSON array contains a string
...te: Here's a demonstration of the performance improvements on a table of 1,000,000 rabbits where each rabbit likes two foods and 10% of them like carrots:
d=# -- Postgres 9.3 solution
d=# explain analyze select info->>'name' from rabbits where exists (
d(# select 1 from json_array_elements(in...
How can I position my div at the bottom of its container?
...argin-top: auto;
}
.parent {
height: 100px;
border: 5px solid #000;
display: flex;
flex-direction: column;
}
.child {
height: 40px;
width: 100%;
background: #f00;
margin-top: auto;
}
<div class="parent">
<div class="child">Align to the bottom</div&...
Why aren't ◎ܫ◎ and ☺ valid JavaScript variable names?
... a single ASCII-only regular expression for JavaScript, it would be over 9,000 characters long. Here it is:
// ECMAScript 5.1 / Unicode v6.3.0:
/^(?!(?:do|if|in|for|let|new|try|var|case|else|enum|eval|null|this|true|void|with|break|catch|class|const|false|super|throw|while|yield|delete|export|impor...