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while (1) Vs. for (;;) Is there a speed difference?
...ase, but chances are the code inside of the loop is going to be a few thousand times more expensive than the loop itself anyway, so who cares?
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Storing a Map using JPA
...o (in the JPA 2.0 specification)
2.6 - Collections of Embeddable Classes and Basic Types
2.7 Map Collections
10.1.11 - ElementCollection Annotation
11.1.29 MapKeyColumn Annotation
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What is the best way to add options to a select from a JavaScript object with jQuery?
...me inside the loop is very wasteful, as is updating the DOM. See points #3 and #6 at artzstudio.com/2009/04/jquery-performance-rules/…
– Patrick
Oct 12 '14 at 7:03
7
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Error : BinderProxy@45d459c0 is not valid; is your activity running?
...log
}
I've been using this to work around the issue on older versions of Android for several years now, and haven't seen the crash since.
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Drop multiple tables in one shot in mysql
How to drop multiple tables from one single database at one command.
something like,
4 Answers
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How to get nice formatting in the Rails console
...
The y method is a handy way to get some pretty YAML output.
y ProductColor.all
Assuming you are in script/console
As jordanpg commented, this answer is outdated. For Rails 3.2+ you need to execute the following code before you can get the y...
Checking for a null int value from a Java ResultSet
...) {
iVal = rs.getInt("ID_PARENT");
if (rs.wasNull()) {
// handle NULL field value
}
}
(Edited as @martin comments below; the OP code as written would not compile because iVal is not initialised)
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How to write a bash script that takes optional input arguments?
...
You could use the default-value syntax:
somecommand ${1:-foo}
The above will, as described in Bash Reference Manual - 3.5.3 Shell Parameter Expansion [emphasis mine]:
If parameter is unset or null, the expansion of word is substituted. Otherwise, the value of paramet...
Can an array be top-level JSON-text?
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Yes, an array is legal as top-level JSON-text.
There are three standard documents defining JSON: RFC 4627, RFC 7159 (which obsoletes RFC 4627), and ECMA-404. They differ in which top-level elements they allow, but all allow an object or an array as the top-level element.
RFC 4627: Object...
How do I space out the child elements of a StackPanel?
...x:Key="tbMargin">0,10,0,0</Thickness>
</Window.Resources>
and then refer to this value in the inner scope
<StackPanel.Resources>
<Style TargetType="{x:Type TextBox}">
<Setter Property="Margin" Value="{StaticResource tbMargin}"/>
</Style>
<...