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What is the difference between HAVING and WHERE in SQL?
...nt(1)
From Address
Where State = 'MA'
Group By City
Gives you a table of all cities in MA and the number of addresses in each city.
This code:
select City, CNT=Count(1)
From Address
Where State = 'MA'
Group By City
Having Count(1)>5
Gives you a table of cities in MA with more than 5 address...
How can I make a div stick to the top of the screen once it's been scrolled to?
... for. I'd like the element to start at 200px below the top of the page (to allow room for other content) and then once the user has scrolled down become fixed at the top.
– evanr
Aug 1 '09 at 8:10
...
Which is faster: Stack allocation or Heap allocation
...
Stack allocation is much faster since all it really does is move the stack pointer.
Using memory pools, you can get comparable performance out of heap allocation, but that comes with a slight added complexity and its own headaches...
How do I restore a missing IIS Express SSL Certificate?
...press, according to such articles as this and this , I am unable to actually load an IIS Express site using HTTPS. In Chrome , I am only getting:
...
In Scala how do I remove duplicates from a list?
...e part of the file name of interest. Once the map is constructed, you can call the values method to get an Iterable of values--the keys will all be distinct by construction.
– Kipton Barros
Dec 19 '12 at 19:47
...
Why do we need C Unions?
...le types together:
enum Type { INTS, FLOATS, DOUBLE };
struct S
{
Type s_type;
union
{
int s_ints[2];
float s_floats[2];
double s_double;
};
};
void do_something(struct S *s)
{
switch(s->s_type)
{
case INTS: // do something with s->s_ints
break;
case F...
How to get year, month, day, hours, minutes, seconds and milliseconds of the current moment in Java?
...t an int to String, make use of String#valueOf().
If your intent is after all to arrange and display them in a human friendly string format, then better use either Java8's java.time.format.DateTimeFormatter (tutorial here),
LocalDateTime now = LocalDateTime.now();
String format1 = now.format(DateTi...
How do I verify that an Android apk is signed with a release certificate?
...oid\sdk\build-tools\25.0.3` (and every other build tools version I had installed)
– Jon
May 15 '17 at 20:17
2
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How to access a preexisting collection with Mongoose?
...
Where in the docs can i find this information? This really helpped but there's no place explaining the plural thing.
– StudioWorks
Apr 7 '14 at 20:31
...
How to get an MD5 checksum in PowerShell
...h = [System.BitConverter]::ToString($md5.ComputeHash([System.IO.File]::ReadAllBytes($someFilePath)))
Starting in PowerShell version 4, this is easy to do for files out of the box with the Get-FileHash cmdlet:
Get-FileHash <filepath> -Algorithm MD5
This is certainly preferable since it a...