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How do I clone a Django model instance object and save it to the database?
...fficial docs on copying model instances: https://docs.djangoproject.com/en/2.2/topics/db/queries/#copying-model-instances
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How to check whether a given string is valid JSON in Java
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263
A wild idea, try parsing it and catch the exception:
import org.json.*;
public boolean isJSO...
Using :after to clear floating elements
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261
Write like this:
.wrapper:after {
content: '';
display: block;
clear: both;
}
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Where can I find a NuGet package for upgrading to System.Web.Http v5.0.0.0?
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Check for array not empty: any?
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251
any? isn't the same as not empty? in some cases.
>> [nil, 1].any?
=> true
>> [...
Heroku Postgres - terminate hung query (idle in transaction)
...s likely to be the query you'd like to terminate. I'll assume the pid is 1234 below.
You may cancel a query through SQL (i.e. without shell access) as long as it's yours or you have super user access:
select pg_cancel_backend(1234);
That's a "friendly" request to cancel the 1234-query, and with...
Include headers when using SELECT INTO OUTFILE?
...d code those headers yourself. Something like:
SELECT 'ColName1', 'ColName2', 'ColName3'
UNION ALL
SELECT ColName1, ColName2, ColName3
FROM YourTable
INTO OUTFILE '/path/outfile'
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matplotlib.pyplot will not forget previous plots - how can I flush/refresh?
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Lock, mutex, semaphore… what's the difference?
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edited Jan 29 '19 at 7:40
answered Feb 25 '10 at 9:21
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