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Set up a scheduled job?
...Django, and I'm curious if there is a way to schedule a job to run periodically.
24 Answers
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Counting null and non-null values in a single query
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If I understood correctly you want to count all NULL and all NOT NULL in a column...
If that is correct:
SELECT count(*) FROM us WHERE a IS NULL
UNION ALL
SELECT count(*) FROM us WHERE a IS NOT NULL
Edited to have the full query, after reading the comments :]
S...
Vim: How to insert in visual block mode?
...capital I.
Lowercase i will not work.
Then type the things you want and finally to apply it to all lines, press Esc twice.
If this doesn't work...
Check if you have +visualextra enabled in your version of Vim.
You can do this by typing in :ver and scrolling through the list of features. (You migh...
How to define a function in ghci across multiple lines?
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For guards (like your example), you can just put them all on one line and it works (guards do not care about spacing)
let abs n | n >= 0 = n | otherwise = -n
If you wanted to write your function with multiple definitions that pattern match on the arguments, like this:
fac...
Is it possible to refresh a single UITableViewCell in a UITableView?
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The OP isn't animating anything, so there's no need to call the begin/endupdates
– kubi
Jul 15 '13 at 17:38
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How to select unique records by SQL
... answered Oct 29 '09 at 5:09
mjalldaymjallday
8,52877 gold badges4747 silver badges6868 bronze badges
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How do you search for files containing DOS line endings (CRLF) with grep on Linux?
...acters. By default it does this it if it decides it's a text file.
-r read all files under each directory recursively.
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How do I make a LinearLayout scrollable?
...it from the adapter functionality of the ListView, then you can simply add all the elements of your list in a LinearLayout wrapper to make it feel all streamlined in the scrollable box along with other elements.
– Atharva
Sep 19 '14 at 10:37
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Append a NumPy array to a NumPy array
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Well, the error message says it all: NumPy arrays do not have an append() method. There's a free function numpy.append() however:
numpy.append(M, a)
This will create a new array instead of mutating M in place. Note that using numpy.append() involves c...
Can you autoplay HTML5 videos on the iPad?
...ugh both script and attribute implementations.
In Safari, on iOS (for all devices, including iPad), where the user may be on a cellular network and be charged per data unit, preload and
auto-play are disabled. No data is loaded until the user initiates it." - Apple documentation.
Here is a ...