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Find rows that have the same value on a column in MySQL
...used addresses first.
SELECT email,
count(*) AS c
FROM TABLE
GROUP BY email
HAVING c > 1
ORDER BY c DESC
If you want the full rows:
select * from table where email in (
select email from table
group by email having count(*) > 1
)
...
How do I sort a list of dictionaries by a value of the dictionary?
I have a list of dictionaries and want each item to be sorted by a specific property values.
18 Answers
...
Why does Ruby have both private and protected methods?
Before I read this article , I thought access control in Ruby worked like this:
7 Answers
...
How to filter by object property in angularJS
... to create a custom filter in AngularJS that will filter a list of objects by the values of a specific property. In this case, I want to filter by the "polarity" property(possible values of "Positive", "Neutral", "Negative").
...
Linq with group by having count
...
Like this:
from c in db.Company
group c by c.Name into grp
where grp.Count() > 1
select grp.Key
Or, using the method syntax:
Company
.GroupBy(c => c.Name)
.Where(grp => grp.Count() > 1)
.Select(grp => grp.Key);
...
Questions every good Java/Java EE Developer should be able to answer? [closed]
...uld realize that there is not problem with it.
So you learned something (by yourself) in the interview and you showed the interviewer that you are able to reason about classes, objects, inheritance, polymorphism, etc. It's actually much better than a candidate who knows the answer by heart but doe...
Kill a Process by Looking up the Port being used by it from a .BAT
...ter name, e.g. %V.
"tokens=4 delims= "
This lets you split up each line by whitespace, and take the 4th chunk in that line, and stuffs it into %variable (in our case, %%P). delims looks empty, but that extra space is actually significant.
netstat -a -n -o
Just run it and find out. According ...
Why are the Level.FINE logging messages not showing?
...ey do not publish the messages to the destinations, which is taken care of by the Handlers. Setting the level of a logger, only causes it to create log records matching that level or higher.
You might be using a ConsoleHandler (I couldn't infer where your output is System.err or a file, but I would...
get dictionary key by value
How do I get a Dictionary key by value in C#?
8 Answers
8
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Structure padding and packing
...ould have offsets, which are mod(4) == 0 on 32-bit platform. Padding is on by default. It inserts the following "gaps" into your first structure:
struct mystruct_A {
char a;
char gap_0[3]; /* inserted by compiler: for alignment of b */
int b;
char c;
char gap_1[3]; /* -"-: for a...