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SQLite - UPSERT *not* INSERT or REPLACE
...e columns in the table: ID, NAME, ROLE
BAD: This will insert or replace all columns with new values for ID=1:
INSERT OR REPLACE INTO Employee (id, name, role)
VALUES (1, 'John Foo', 'CEO');
BAD: This will insert or replace 2 of the columns... the NAME column will be set to NULL or the def...
Random row selection in Pandas dataframe
... Thanks @eumiro. I also worked out that df.ix[np.random.random_integers(0, len(df), 10)] would also work.
– John
Apr 10 '13 at 10:58
7
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Select random row from a sqlite table
... the day seeded with unix epoc for today at noon so it shows the same book all day even if the query is run multiple times. Yes I know caching is more efficient for this use case just an example.
– danielson317
Apr 22 at 17:18
...
How to call asynchronous method from synchronous method in C#?
I have a public async void Foo() method that I want to call from synchronous method. So far all I have seen from MSDN documentation is calling async methods via async methods, but my whole program is not built with async methods.
...
Changing a specific column name in pandas DataFrame
...
A one liner does exist:
In [27]: df=df.rename(columns = {'two':'new_name'})
In [28]: df
Out[28]:
one three new_name
0 1 a 9
1 2 b 8
2 3 c 7
3 4 d 6
4 5 e 5
Following is the docstring for the rename method.
De...
Determine if Android app is being used for the first time
...
Beware for Android 6.0 (API 23 - Marshmallow) or above auto backup (developer.android.com/guide/topics/data/autobackup.html)is enabled by default. If the users uninstalls and then reinstalls the app the shared preferences will be recovered. So on reinstalls you ca...
Get current time in milliseconds in Python?
...illis = int(round(time.time() * 1000))
print millis
Quick'n'easy. Thanks all, sorry for the brain fart.
For reuse:
import time
current_milli_time = lambda: int(round(time.time() * 1000))
Then:
>>> current_milli_time()
1378761833768
...
Auto Resize Image in CSS FlexBox Layout and keeping Aspect Ratio?
... it also possible to do this for the height dimension if the screen gets smaller?
– confile
Jan 14 '14 at 0:43
@confil...
Call PowerShell script PS1 from another PS1 script inside Powershell ISE
...$ChromeInstallArgs= "/i", "$PSScriptRoot\googlechromestandaloneenterprise64_v.57.0.2987.110.msi", "/q", "/norestart", "/L*v `"C:\Windows\Logs\Google_Chrome_57.0.2987.110_Install_x64.log`""
Start-Process -FilePath msiexec -ArgumentList $ChromeInstallArgs -Wait -ErrorAction Stop
$Result= [Syst...
Loading and parsing a JSON file with multiple JSON objects
... contains JSON per line, you are saved the headaches of trying to parse it all in one go or to figure out a streaming JSON parser. You can now opt to process each line separately before moving on to the next, saving memory in the process. You probably don't want to append each result to one list and...