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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...
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
...
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...
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 run SQL script in MySQL?
...ing '/' instead of '\' worked correctly for me. I got errors when I originally used '/'. This is what worked for me...source C:/Users/macombers/Downloads/midcoast_db.sql;
– Zack Macomber
Oct 3 '14 at 15:09
...
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...
Launch Bootstrap Modal on page load
I don't know javascript at all. The bootstrap documentation says to
18 Answers
18
...
Pimpl idiom vs Pure virtual class interface
...by "value". Often, doesn't make sense to "copy" instances of the class at all. When it does make sense, a polymorphic "Clone" method is usually more appropriate. Examples: A Socket class, a Database class, a "policy" class, anything that would be a "closure" in a functional language.
Both pImpl ...