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JPA EntityManager: Why use persist() over merge()?
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I noticed that when I used em.merge, I got a SELECT statement for every INSERT, even when there was no field that JPA was generating for me--the primary key field was a UUID that I set myself. I switched to em.persist(myEntityObject) and got just INSERT statements then...
Why use the params keyword?
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You could also use return args.Select(x => x + 2).Sum();
– bbvg
Aug 22 '17 at 21:07
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Unique (non-repeating) random numbers in O(1)?
... max
At each iteration, a random number r is selected between 0 and max, array[r] and array[max] are swapped, the new array[max] is returned, and max is decremented:
max = 10, r = 3
+--------------------+
v v
+--+--+--+--+--+--+...
Input placeholders for Internet Explorer
...n(){
if (input.val() === text) input.css({ color:'lightGrey' }).selectRange(0,0).one('keydown', function(){
input.val("").css({ color:'black' });
});
});
input.blur(function(){
if (input.val() == "" || input.val() === text) input.val(text)...
How do you remove the root CA certificate that fiddler installs
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Are you sure you don't need to first deselect the "Decrypt HTTPS traffic", then choose "Remove Interception Certificates"?
– bozzle
Apr 18 '17 at 0:51
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Why does this async action hang?
...DBConnection.ExecuteAsync<ResultClass>(
ds => ds.Execute("select slow running data into result"));
}
What's the difference? There's now no awaiting anywhere, so nothing being implicitly scheduled to the UI thread. For simple methods like these that have a single return, there's no...
How to generate a number of most distinctive colors in R?
...the colorBrewer package (and website). If you want diverging colours, then select diverging on the site. For example,
library(colorBrewer)
brewer.pal(7, "BrBG")
The I want hue web site gives lots of nice palettes. Again, just select the palette that you need. For example, you can get the rgb col...
How can I give the Intellij compiler more heap space?
...er give value -Xmx512m.
Intelij Setting Options
2). Go to Control Pannel Select View by :Large icons then Go to Java one promp window will appear with name java control pannel then go to java
Java VM Options
select view option.
java view options
In Java Run time Environment Setting pass Run tim...
“Java DateFormat is not threadsafe” what does this leads to?
...eFormat object and called its format() for values read via JDBC. I had SQL select statement where I read the same date with different names (SELECT date_from, date_from AS date_from1 ...). Such statements were using in 5 threads for various dates in WHERE clasue. Dates looked "normal" but they diffe...
Install Gem from Github Branch?
...file.5.html#GIT
Update: There's a github source identifier.
gem 'country_select', github: 'stefanpenner/country_select'
However, they warn against using it: NOTE: This shorthand should be avoided until Bundler 2.0, since it currently expands to an insecure git:// URL. This allows a man-in-the-mi...