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How to check if a database exists in SQL Server?
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In general it's because Microsoft commits to the format INFORMATION_SCHEMA, and reserves the right to change the system tables as they please. But in this case, after looking more closely, INFORMATION_SCHEMA doesn't work, so this is probably ...
How can I tell PyCharm what type a parameter is expected to be?
When it comes to constructors, and assignments, and method calls, the PyCharm IDE is pretty good at analyzing my source code and figuring out what type each variable should be. I like it when it's right, because it gives me good code-completion and parameter info, and it gives me warnings if I try t...
How to define a custom ORDER BY order in mySQL
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MySQL has a handy function called FIELD() which is excellent for tasks like this.
ORDER BY FIELD(Language,'ENU','JPN','DAN'), ID
Note however, that
It makes your SQL less portable, as other DBMSs might not have such function
When your list of langu...
Convert a row of a data frame to vector
...changed in the meantime, but today unlist allows dropping names: identical(unlist(df[1,], use.names = FALSE), as.numeric(df[1,])) (and btw df still is not a sensible name for a data.frame... ;-))
– Andri Signorell
Sep 25 '19 at 13:51
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Django admin: how to sort by one of the custom list_display fields that has no database field
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I loved Greg's solution to this problem, but I'd like to point that you can do the same thing directly in the admin:
from django.db import models
class CustomerAdmin(admin.ModelAdmin):
list_display = ('number_of_orders',)
def get_queryset(self, request):
# def queryset(self, reques...
Changing the color of the axis, ticks and labels for a plot in matplotlib
...a quick example (using a slightly cleaner method than the potentially duplicate question):
import matplotlib.pyplot as plt
fig = plt.figure()
ax = fig.add_subplot(111)
ax.plot(range(10))
ax.set_xlabel('X-axis')
ax.set_ylabel('Y-axis')
ax.spines['bottom'].set_color('red')
ax.spines['top'].set_col...
Can the C# interactive window interact with my code?
In Visual Studio 2015 or later, I can open the 'C# interactive window', and run code:
5 Answers
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How does @synchronized lock/unlock in Objective-C?
...nguage level synchronization uses the mutex, just like NSLock does. Semantically there are some small technical differences, but it is basically correct to think of them as two separate interfaces implemented on top of a common (more primitive) entity.
In particular with a NSLock you have an explic...
Difference between an application server and a servlet container?
I am trying to understand the difference between a full fledged application server (e.g. Weblogic, JBoss etc.) and a servlet container (Tomcat, Jetty etc.).
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Are there any downsides to enabling git rerere?
...ault. So is there any downside to enabling rerere? What potential problems can it cause that would not otherwise occur?
4 A...