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Cloning an Object in Node.js
...ion is now marked as deprecated in the documentation of Node.js:
The util._extend() method was never intended to be used outside of internal Node.js modules. The community found and used it anyway.
It is deprecated and should not be used in new code. JavaScript comes with very similar built-in func...
MySQL check if a table exists without throwing an exception
...PDO syntax for it, but this seems pretty straight-forward:
$result = mysql_query("SHOW TABLES LIKE 'myTable'");
$tableExists = mysql_num_rows($result) > 0;
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...
#1071 - Specified key was too long; max key length is 1000 bytes
...per column as you define the index. For example:
...
KEY `index` (`parent_menu_id`,`menu_link`(50),`plugin`(50),`alias`(50))
...
But what's the best prefix length for a given column? Here's a method to find out:
SELECT
ROUND(SUM(LENGTH(`menu_link`)<10)*100/COUNT(`menu_link`),2) AS pct_leng...
Skip certain tables with mysqldump
...!/bin/bash
PASSWORD=XXXXXX
HOST=XXXXXX
USER=XXXXXX
DATABASE=databasename
DB_FILE=dump.sql
EXCLUDED_TABLES=(
table1
table2
table3
table4
tableN
)
IGNORED_TABLES_STRING=''
for TABLE in "${EXCLUDED_TABLES[@]}"
do :
IGNORED_TABLES_STRING+=" --ignore-table=${DATABASE}.${TABLE}"
done
echo "Dump st...
How do I use installed packages in PyCharm?
...ere you can import the module.
>> import gnuradio
>> gnuradio.__file__
"path/to/gnuradio"
Most commonly you'll have a folder structure like this:
foobarbaz/
gnuradio/
__init__.py
other_file.py
You want to add foobarbaz to the path here.
...
Does C# have extension properties?
...{
private static readonly ConditionalWeakTable<Person, Employee> _employees =
new ConditionalWeakTable<Person, Employee>();
public decimal Salary
{
get
{
// `this` is the instance of Person
return _employees.GetOrCreate(this...
Iterating C++ vector from the end to the beginning
...
The best way is:
for (vector<my_class>::reverse_iterator i = my_vector.rbegin();
i != my_vector.rend(); ++i ) {
}
rbegin()/rend() were especially designed for that purpose. (And yes, incrementing a reverse_interator moves it backward.)
Now...
How to check for null in Twig?
... Notice: as Twig 2.x check for variable is equal to value like is_ sameas must be {% if var is same as(false) %} not {% if var is sameas(false) %} see Doc url => twig.symfony.com/doc/2.x/tests/sameas.html
– ahmed hamdy
Jul 15 '19 at 17:01
...
Why does changing 0.1f to 0 slow down performance by 10x?
...Here's the test code compiled on x64:
int main() {
double start = omp_get_wtime();
const float x[16]={1.1,1.2,1.3,1.4,1.5,1.6,1.7,1.8,1.9,2.0,2.1,2.2,2.3,2.4,2.5,2.6};
const float z[16]={1.123,1.234,1.345,156.467,1.578,1.689,1.790,1.812,1.923,2.034,2.145,2.256,2.367,2.478,2.589,2.690}...
Is it worth using Python's re.compile?
...e.py (comments are mine):
def match(pattern, string, flags=0):
return _compile(pattern, flags).match(string)
def _compile(*key):
# Does cache check at top of function
cachekey = (type(key[0]),) + key
p = _cache.get(cachekey)
if p is not None: return p
# ...
# Does act...