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In SQL, what's the difference between count(column) and count(*)?
... rows having a non-null value on the rows.
Please see following code for test executions SQL Server 2008:
-- Variable table
DECLARE @Table TABLE
(
CustomerId int NULL
, Name nvarchar(50) NULL
)
-- Insert some records for tests
INSERT INTO @Table VALUES( NULL, 'Pedro')
INSERT INTO @Tab...
Performance difference for control structures 'for' and 'foreach' in C#
...L_002f: endfinally
} // end handler
IL_0030: ret
} // end of method Test::IterateOverList
The compiler treats arrays differently, converting a foreach loop basically to a for loop, but not List<T>. Here's the equivalent code for an array:
static void IterateOverArray(object[] array)
...
How do I grab an INI value within a shell script?
...
Just include your .ini file into bash body:
File example.ini:
DBNAME=test
DBUSER=scott
DBPASSWORD=tiger
File example.sh
#!/bin/bash
#Including .ini file
. example.ini
#Test
echo "${DBNAME} ${DBUSER} ${DBPASSWORD}"
...
Setting “checked” for a checkbox with jQuery
...('checked', false);
Note that this is the approach used by jQuery's unit tests prior to version 1.6 and is preferable to using $('.myCheckbox').removeAttr('checked'); since the latter will, if the box was initially checked, change the behaviour of a call to .reset() on any form that contains it ...
How to sort by two fields in Java?
...es it a bit more clunky to define compared to LINQ.
Here is the full unit test for reference:
@Test
public void testChainedSorting()
{
// Create the collection of people:
ArrayList<Person> people = new ArrayList<>();
people.add(new Person("Dan", 4));
people.add(new Pers...
How to determine if a type implements an interface with C# reflection
...ud: IsAssignableFrom does eventually calls GetInterfaces, so probably your test checked the GetInterfaces first and IsAssignable after. That is because GetInterfaces caches it's results so the first invocation costs more
– Panos Theof
Oct 11 '13 at 11:23
...
A numeric string as array key in PHP
...ill not be cast, as it isn't a valid decimal integer., although I have not tested his answer.
– steampowered
Apr 19 '16 at 13:04
...
SQL is null and = null [duplicate]
...ows by coding where my_column = null.
SQL provides the special syntax for testing if a column is null, via is null and is not null, which is a special condition to test for a null (or not a null).
Here's some SQL showing a variety of conditions and and their effect as per above.
create table t (x...
Map implementation with duplicate keys
...f course. It just eases your life, as you don't have to re-implement them, test them, etc.
– PhiLho
Jul 30 '13 at 12:51
...
StringIO in Python3
...ule StringIO is gone and from io import BytesIO should be applied instead. Tested myself on python 3.5 @ eclipse pyDev + win7 x64. Please let me know if I were wrong thanks.
– Bill Huang
Mar 5 '16 at 17:16
...