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Confusion: @NotNull vs. @Column(nullable = false) with JPA and Hibernate
...icks up on these constraints and translates them into database constraints for you, so you get two for the price of one. @Column(nullable = false) is the JPA way of declaring a column to be not-null. I.e. the former is intended for validation and the latter for indicating database schema details. Yo...
Android Preferences: How to load the default values when the user hasn't used the preferences-screen
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Take a look into PreferenceManager.setDefaultValues in Android API for further investigation.
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Match multiple cases classes in scala
...println(aString)"? Seems like as long as the type of aString is identical for both A and B, it should be allowed. Your last example seems like it would be better off not duplicating the B and C cases.
– James Moore
Nov 9 '11 at 1:18
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Cause of a process being a deadlock victim
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Q1:Could the time it takes for a transaction to execute make the associated process more likely to be flagged as a deadlock victim.
No. The SELECT is the victim because it had only read data, therefore the transaction has a lower cost associated with...
What is a PDB file?
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A PDB file contains information for the debugger to work with. There's less information in a Release build than in a Debug build anyway. But if you want it to not be generated at all, go to your project's Build properties, select the Release confi...
Group by with multiple columns using lambda
... Would this actually work? I would think that the equality test for each object you're grouping by would fail since they're objects and not structs.
– Jacob
Aug 4 '11 at 2:17
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HTML5 Canvas vs. SVG vs. div
What is the best approach for creating elements on the fly and being able to move them around? For example, let's say I want to create a rectangle, circle and polygon and then select those objects and move them around.
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Change timestamps while rebasing git branch
I have reorganized the commits in a branch before it is going to be made public causing the timestamps of the commits to be in an mixed up order. I would rather have them be all be today with only seconds in between.
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Why can't enum's constructor access static fields?
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The constructor is called before the static fields have all been initialized, because the static fields (including those representing the enum values) are initialized in textual order, and the enum values always come before the other fields. Note that i...
Global and local variables in R
I am a newbie for R, and I am quite confused with the usage of local and global variables in R.
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