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What is a word boundary in regex?
...oundary, in most regex dialects, is a position between \w and \W (non-word char), or at the beginning or end of a string if it begins or ends (respectively) with a word character ([0-9A-Za-z_]).
So, in the string "-12", it would match before the 1 or after the 2. The dash is not a word character.
...
Table name as variable
...mpare data between the same tables of different databases:
static query:
SELECT * FROM [DB_ONE].[dbo].[ACTY]
EXCEPT
SELECT * FROM [DB_TWO].[dbo].[ACTY]
since I want easily change tha name of table and schema I have created this dynamic query:
declare @schema varchar(50)
declare @table varchar(5...
Average of 3 long integers
... - 1;
long z = long.MaxValue - 2;
long[] arr = { x, y, z };
var avg = arr.Select(i => i / arr.Length).Sum()
+ arr.Select(i => i % arr.Length).Sum() / arr.Length;
share
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improve thi...
Do I have to guard against SQL injection if I used a dropdown?
...
$size = filter_input(INPUT_POST, "size", FILTER_VALIDATE_INT);
echo '<select name="size">';
foreach($sizes as $i => $s) {
echo '<option value="' . $i . '"' . ($i == $size ? ' selected' : '') . '>' . $s . '</option>';
}
echo '</select>';
Then you can use $size in yo...
How to rename items in values() in Django?
... a bit hacky, but you could use the extra method:
MyModel.objects.extra(
select={
'renamed_value': 'cryptic_value_name'
}
).values(
'renamed_value'
)
This basically does SELECT cryptic_value_name AS renamed_value in the SQL.
Another option, if you always want the renamed version but the d...
How to map and remove nil values in Ruby
...blem:
N = 1_00_000
enum = 1.upto(1_000)
Benchmark.bmbm do |x|
x.report("select + map") { N.times { enum.select { |i| i.even? }.map{|i| i + 1} } }
x.report("map + compact") { N.times { enum.map { |i| i + 1 if i.even? }.compact } }
x.report("filter_map") { N.times { enum.filter_map { |i| i ...
(grep) Regex to match non-ASCII characters?
... Linux, I have a directory with lots of files. Some of them have non-ASCII characters, but they are all valid UTF-8 . One program has a bug that prevents it working with non-ASCII filenames, and I have to find out how many are affected. I was going to do this with find and then do a grep to pri...
Check if a string contains a string in C++
...lt;chrono>
std::string randomString( size_t len );
int main(int argc, char* argv[])
{
using namespace std::chrono;
const size_t haystacksCount = 200000;
std::string haystacks[haystacksCount];
std::string needle = "hello";
bool sink = true;
high...
How to pass an array within a query string?
...)
Form Examples
On a form, multi-valued fields could take the form of a select box set to multiple:
<form>
<select multiple="multiple" name="cars[]">
<option>Volvo</option>
<option>Saab</option>
<option>Mercedes</option...
python pandas remove duplicate columns
...,False,True].
Pandas allows one to index using boolean values whereby it selects only the True values. Since we want to keep the unduplicated columns, we need the above boolean array to be flipped (ie [True, True, False] = ~[False,False,True])
Finally, df.loc[:,[True,True,False]] selects only the...