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How do I delete multiple rows in Entity Framework (without foreach)
...Expression<Func<T, bool>> filter) where T : class
{
string selectSql = db.Set<T>().Where(filter).ToString();
string fromWhere = selectSql.Substring(selectSql.IndexOf("FROM"));
string deleteSql = "DELETE [Extent1] " + fromWhere;
db.Database.ExecuteSqlCommand(deleteSq...
Regular expression to match DNS hostname or IP Address?
...check separately that the total length of the hostname must not exceed 255 characters. For more information, please consult RFC-952 and RFC-1123.
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How do I hide an element on a click event anywhere outside of the element?
... you have other elements inside .myDiv element. For example, if you have a select dropdown inside .myDiv. When you click the select, it will think youre clicking outside the box.
– CodeGodie
Nov 22 '16 at 15:13
...
How to select rows with one or more nulls from a pandas DataFrame without listing columns explicitly
... 0.0 NaN 0.0
3 0.0 1.0 2.0 3.0
4 NaN 0.0 NaN NaN
If you want to select the rows that have two or more columns with null value, you run the following:
>>> qty_of_nuls = 2
>>> df.iloc[df[(df.isnull().sum(axis=1) >=qty_of_nuls)].index]
0 1 2 3
1 0.0 NaN 0...
Get PostGIS version
...s like GEOS and proj4 you might want to get their versions too. Then use:
SELECT PostGIS_full_version();
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How can we prepend strings with StringBuilder?
... O(n^2) time.
A naive approach would be to add an offset into the backing char[] buffer as well as the length. When there is not enough room for a prepend, move the data up by more than is strictly necessary. This can bring performance back down to O(n log n) (I think). A more refined approach is t...
How to do a join in linq to sql with method syntax?
...eOtherClass
on sc.Property1 equals soc.Property2
select new { SomeClass = sc, SomeOtherClass = soc };
Would be equivalent to:
var result = enumerableOfSomeClass
.Join(enumerableOfSomeOtherClass,
sc => sc.Property1,
soc => soc.Property2,
...
Can an enum class be converted to the underlying type?
...t16_t /*v*/) {
std::cout << "uint16_t!\n";
}
int main(int argc, char* argv[]) {
SomeEnum e = B;
write(util::underlying_cast(e));
return 0;
}
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MySQL CONCAT returns NULL if any field contain NULL
...
convert the NULL values with empty string by wrapping it in COALESCE
SELECT CONCAT(COALESCE(`affiliate_name`,''),'-',COALESCE(`model`,''),'-',COALESCE(`ip`,''),'-',COALESCE(`os_type`,''),'-',COALESCE(`os_version`,'')) AS device_name
FROM devices
...
How do I reverse a C++ vector?
...am>
template<class InIt>
void print_range(InIt first, InIt last, char const* delim = "\n"){
--last;
for(; first != last; ++first){
std::cout << *first << delim;
}
std::cout << *first;
}
int main(){
int a[] = { 1, 2, 3, 4, 5 };
std::vector<int> v(a, ...