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Create a list from two object lists with linq
...ite a lot to this:
list1.Concat(list2)
.ToLookup(p => p.Name)
.Select(g => g.Aggregate((p1, p2) => new Person
{
Name = p1.Name,
Value = p1.Value,
Change = p2.Value - p1.Value
}));
Although this won't error in the case where you have duplicate na...
Hide files with certain extension in Sublime Text Editor?
...
Are you talking about the sidebar? For example, if you select File → Open and select a folder, then the folder and its contents are displayed along the left side, allowing you to navigate amongst its contents and sub-directories. If that is the case, then the answer is yes, fi...
Returning IEnumerable vs. IQueryable
...mers = custs.Where(c => c.IsGold);
That code will execute SQL to only select gold customers. The following code, on the other hand, will execute the original query in the database, then filtering out the non-gold customers in the memory:
IEnumerable<Customer> custs = ...;
// Later on...
...
How to deal with SettingWithCopyWarning in Pandas?
...owing, which does not always work as expected, particularly when the first selection returns a copy. [see GH5390 and GH5597 for background discussion.]
df[df['A'] > 2]['B'] = new_val # new_val not set in df
The warning offers a suggestion to rewrite as follows:
df.loc[df['A'] > 2, 'B'] =...
SQL UPDATE all values in a field with appended string CONCAT not working
...
That's pretty much all you need:
mysql> select * from t;
+------+-------+
| id | data |
+------+-------+
| 1 | max |
| 2 | linda |
| 3 | sam |
| 4 | henry |
+------+-------+
4 rows in set (0.02 sec)
mysql> update t set data=concat(data, 'a');...
what is reverse() in Django
... question = get_object_or_404(Question, pk=question_id)
try:
selected = question.choice_set.get(pk=request.POST['choice'])
except KeyError:
# handle exception
pass
else:
selected.votes += 1
selected.save()
return HttpResponseRedirect(reve...
Disable spell checking on IntelliJ IDEA
...u can either:
Disable spell checking entirely, or
Disable spell checking selectively (e.g. just the code), but enable for some others (e.g. comments).
I'm on MacOS Webstorm (version 2016.1.2). First thing first, go to the "Inspection" pane like this...
Webstorm -> Preferences -> search fo...
How do you list all triggers in a MySQL database?
...w triggers;
or you can access the INFORMATION_SCHEMA table directly by:
select trigger_schema, trigger_name, action_statement
from information_schema.triggers
You can do this from version 5.0.10 onwards.
More information about the TRIGGERS table is here.
...
What is the direction of stack growth in most modern systems?
... else's code.
The processors and their direction are:
x86: down.
SPARC: selectable. The standard ABI uses down.
PPC: down, I think.
System z: in a linked list, I kid you not (but still down, at least for zLinux).
ARM: selectable, but Thumb2 has compact encodings only for down (LDMIA = increment ...
INNER JOIN vs LEFT JOIN performance in SQL Server
...(ID, Name) VALUES (4, 'Four')
INSERT #Test2 (ID, Name) VALUES (5, 'Five')
SELECT *
FROM #Test1 t1
INNER JOIN #Test2 t2
ON t2.Name = t1.Name
SELECT *
FROM #Test1 t1
LEFT JOIN #Test2 t2
ON t2.Name = t1.Name
DROP TABLE #Test1
DROP TABLE #Test2
If you run this and view the execution plan, you'll se...