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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...
Sockets: Discover port availability using Java
...ee = false;
}
return portFree;
}
EDIT: If all you're trying to do is select a free port then new ServerSocket(0) will find one for you.
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MySQL check if a table exists without throwing an exception
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If you're using MySQL 5.0 and later, you could try:
SELECT COUNT(*)
FROM information_schema.tables
WHERE table_schema = '[database name]'
AND table_name = '[table name]';
Any results indicate the table exists.
From: http://www.electrictoolbox.com/check-if-mysql-table-exis...
How to change Navigation Bar color in iOS 7?
... You can also use if ([self.navigationController.navigationBar respondsToSelector:@selector(setBarTintColor:)]) vs the version number to check if you can set the barTintColor
– SimpsOff
Dec 24 '13 at 17:32
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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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ASP.NET MVC Yes/No Radio Buttons with Strongly Bound Model MVC
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The second parameter is selected, so use the ! to select the no value when the boolean is false.
<%= Html.RadioButton("blah", !Model.blah) %> Yes
<%= Html.RadioButton("blah", Model.blah) %> No
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Why does Hibernate require no argument constructor?
...please look at my problem How to write HQL JOIN query for multiple table's selected Columns using Constructor In The Select Clause
– Shantaram Tupe
Dec 9 '17 at 9:33
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How to add spacing between UITableViewCell
... @Husam Your solution worked for me. But I have a problem when selected cell. I have set the border for contentView and whenever I selected cell the border will be smaller. How can I fix it?
– Bad_Developer
Mar 24 '17 at 11:09
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Can't execute jar- file: “no main manifest attribute”
...o specify the Application's entry point in eclipse.
When you say Export,
Select Jar and next
[ give it a name in the next window ] and next
and next again
and you'll see " Select the class of the application entry point".
Just pick a class and Eclipse will automatically build a cool MANIFEST....
Local file access with JavaScript
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If the user selects a file via <input type="file">, you can read and process that file using the File API.
Reading or writing arbitrary files is not allowed by design. It's a violation of the sandbox. From Wikipedia -> Javascri...