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How can I see the raw SQL queries Django is running?
...ueries:
from django.db import connection
print(connection.queries)
Querysets also have a query attribute containing the query to be executed:
print(MyModel.objects.filter(name="my name").query)
Note that the output of the query is not valid SQL, because:
"Django never actually interpolates...
What's a quick way to comment/uncomment lines in Vim?
I have a Ruby code file open in vi, there are lines commented out with # :
46 Answers
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PostgreSQL: Drop PostgreSQL database through command line [closed]
...y, after saying, "SSL connection closed unexpectedly [...] attempting to reset: Succeeded." Annnd, I'm back.
– mlissner
Nov 12 '18 at 19:03
add a comment
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How to detect unused methods and #import in Objective-C
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Xcode allows you to (un)check settings for specific compiler warnings that can warn you of some types of unused code. (Select the project in the source list and File > Get Info, then select the Build tab.) Here are a few (which show up for Clang and GC...
Remove non-ascii character in string
... least IE 11). It fails with error: SCRIPT5021: Invalid range in character set
– Andrey Sorich
May 19 '19 at 6:51
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How to get a pixel's x,y coordinate color from an image?
... 0, img.width, img.height);
After that, when a user clicks, use event.offsetX and event.offsetY to get the position. This can then be used to acquire the pixel:
var pixelData = canvas.getContext('2d').getImageData(event.offsetX, event.offsetY, 1, 1).data;
Because you are only grabbing one pixe...
#1071 - Specified key was too long; max key length is 767 bytes
...t has been increased to 3072 bytes.
You also have to be aware that if you set an index on a big char or varchar field which is utf8mb4 encoded, you have to divide the max index prefix length of 767 bytes (or 3072 bytes) by 4 resulting in 191. This is because the maximum length of a utf8mb4 characte...
Setting a system environment variable from a Windows batch file?
Is it possible to set a environment variable at the system level from a command prompt in Windows 7 (or even XP for that matter). I am running from an elevated command prompt.
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How to delete a row by reference in data.table?
...taken in order to make memory use be similar to in-place deletion is to subset a column at a time and delete. not as fast as a proper C memmove solution, but memory use is all i care about here. something like this:
DT = data.table(col1 = 1:1e6)
cols = paste0('col', 2:100)
for (col in cols){ DT[, (...
Matplotlib scatterplot; colour as a function of a third variable
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There's no need to manually set the colors. Instead, specify a grayscale colormap...
import numpy as np
import matplotlib.pyplot as plt
# Generate data...
x = np.random.random(10)
y = np.random.random(10)
# Plot...
plt.scatter(x, y, c=y, s=500)
plt.g...