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Efficient SQL test query or validation query that will work across all (or most) databases
...for idleness. For example, the JDBC pooling library c3p0 has a property called preferredTestQuery , which gets executed on the connection at configured intervals. Similarly, Apache Commons DBCP has validationQuery .
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What is the best django model field to use to represent a US dollar amount?
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I think this example is correct almost to all currencies. To represent currencies as Bitcoin, I think is much better to use an integer field to save the amount in satoshis, and then show it to the final user in the representation that you want (BTC, mBTC, etc)
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HTTP Basic Authentication - what's the expected web browser experience?
When a server allows access via Basic HTTP Authentication, what is the experience expected to be in a web browser ?
6 Answ...
What is the exact meaning of Git Bash?
... , fetch , and merge . But I still don't know what Git Bash itself actually is!
4 Answers
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Pandas aggregate count distinct
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How about either of:
>>> df
date duration user_id
0 2013-04-01 30 0001
1 2013-04-01 15 0001
2 2013-04-01 20 0002
3 2013-04-02 15 0002
4 2013-04-02 30 0002
>>> df.groupby("date").agg({"duration": np.sum, "use...
How do I find the .NET version?
How do I find out which version of .NET is installed?
19 Answers
19
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Run an app on a multiple devices automatically in Android Studio
... device. Is there any way to deploy the app on a multiple devices automatically - by clicking Run or even better with a shortcut?
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How do I encode and decode a base64 string?
..., I'll agree that wrapping a deref error is definitely dubious (plus we're all slowly agreeing to the fact that null as a concept is a bit of a hack to begin with), but we can still see some effects otherwise: the parameter name given in the exception might not be correct if left unchecked.
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Getting time elapsed in Objective-C
...er to use Apple's function CACurrentMediaTime!
I also benchmarked the mach_timebase_info call and it takes approximately 19ns on my iPhone 6, so I removed the (not threadsafe) code which was caching the output of that call.
#include <mach/mach.h>
#include <mach/mach_time.h>
uint64_t g...
Twitter Bootstrap: div in container with 100% height
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The #map is actually obscured behind the navbar in this example.
– Ethereal
May 7 '13 at 19:57
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