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What is database pooling?
...eeps the connections active so that, when a connection is later requested, one of the active ones is used in preference to having to create another one.
Refer to the following diagram for the next few paragraphs:
+---------+
| |
| Clients |
+---------+ |
| |-+ (1) +------+...
Hidden features of Ruby
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I actually wrote an gem at one point to do this, but my code was (a) a mess, and (b) slow. I'm very glad that the functionality has made it into core.
– James A. Rosen
Dec 14 '09 at 13:47
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JPA: unidirectional many-to-one and cascading delete
Say I have a unidirectional @ManyToOne relationship like the following:
7 Answers
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Using a piano keyboard as a computer keyboard [closed]
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I haven't done any MIDI programming in years, but your fundamental idea is very sound (no pun).
MIDI is a stream of "events" (or "messages"), two of the most fundamental being "note on" and "note off" which carry with them the note num...
Why would one use nested classes in C++?
Can someone please point me towards some nice resources for understanding and using nested classes? I have some material like Programming Principles and things like this IBM Knowledge Center - Nested Classes
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Difference between del, remove and pop on lists
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Remember guys... anything index based is one shot O(n-1)... if you have to do a lookup (by value), it will traverse the collection until the element is found.
– Pepito Fernandez
Oct 14 '17 at 14:13
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How can I download a specific Maven artifact in one command line?
...cing your copy of maven to use a given version of a plugin.
This can be done as follows:
1. Add the following line within the <settings> element of your ~/.m2/settings.xml file:
<usePluginRegistry>true</usePluginRegistry>
2. Add the file ~/.m2/plugin-registry.xml with the f...
Creating a constant Dictionary in C#
...constant dictionary in C# is not really a straightforward task. Actually, none of the answers here really achieve that.
There is one solution though which meets your requirements, although not necessarily a nice one; remember that according to the C# specification, switch-case tables are compiled t...
Pandas selecting by label sometimes return Series, sometimes returns DataFrame
In Pandas, when I select a label that only has one entry in the index I get back a Series, but when I select an entry that has more then one entry I get back a data frame.
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Why Qt is misusing model/view terminology?
...t's naming is misleading. In my opinion however, the problem is not Qt's alone, but is shared by all frameworks that allow us to adhere to the principle of separation of concerns when implementing our UIs. When someone comes up with such a framework, and finds a good way to keep "things" separated, ...