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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');...
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...
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Hide files with certain extension in Sublime Text Editor?
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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...
Difference between int32, int, int32_t, int8 and int8_t
... in a C program recently. I know that it stores 32 bits, but don't int and int32 do the same?
3 Answers
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“From View Controller” disappears using UIViewControllerContextTransitioning
I got one problem and i have described it below.
17 Answers
17
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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'] =...
What is the reason for performing a double fork when creating a daemon?
...curious as to why a double fork is necessary. I've scratched around google and found plenty of resources declaring that one is necessary, but not why.
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Custom toast on Android: a simple example
I'm new to Android programming. What is a simple example showing a custom toast notification on Android?
17 Answers
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Open a URL in a new tab (and not a new window)
... demonstrate this.)
CSS3 proposed target-new, but the specification was abandoned.
The reverse is not true; by specifying dimensions for the window in the third argument of window.open(), you can trigger a new window when the preference is for tabs.
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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...