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What is the difference between CascadeType.REMOVE and orphanRemoval in JPA?
...s address;
:
}
Orphan Removal
JPA 2 supports an additional and more aggressive remove cascading mode
which can be specified using the orphanRemoval element of the
@OneToOne and @OneToMany annotations:
@Entity
class Employee {
:
@OneToOne(orphanRemoval=true)
private ...
How to fix 'android.os.NetworkOnMainThreadException'?
I got an error while running my Android project for RssReader.
59 Answers
59
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How do you specify the date format used when JAXB marshals xsd:dateTime?
...ery difficult to reproduce in normal testing, but under load could happen, and would be exceedingly difficult to diagnose. It's better to create a new SimpleDateFormat with marshal and unmarshal (but use a static format string if necessary).
– Colselaw
Feb 28 '...
Header files for x86 SIMD intrinsics
...d normally just include <immintrin.h>. It includes everything.
GCC and clang will stop you from using intrinsics for instructions you haven't enabled at compile time (e.g. with -march=native or -mavx2 -mbmi2 -mpopcnt -mfma -mcx16 -mtune=znver1 or whatever.)
MSVC and ICC will let you use int...
How to use Swift @autoclosure
...})
// "It's true"
If we omit the braces, we are passing in an expression and that's an error:
f(pred: 2 > 1)
// error: '>' produces 'Bool', not the expected contextual result type '() -> Bool'
@autoclosure creates an automatic closure around the expression. So when the caller writes an...
OAuth with Verification in .NET
...en-source OAuth support classes available for .NET apps are hard to understand, overly complicated (how many methods are exposed by DotNetOpenAuth?), poorly designed (look at the methods with 10 string parameters in the OAuthBase.cs module from that google link you provided - there's no state manage...
How do I execute inserts and updates in an Alembic upgrade script?
...ms.
Note that Alembic provides some basic data functions: op.bulk_insert() and op.execute(). If the operations are fairly minimal, use those. If the migration requires relationships or other complex interactions, I prefer to use the full power of models and sessions as described below.
The followi...
What is the difference between “Rollback…” and “Back Out Submitted Changelist #####” in Perforce P4V
...
Both of these operations restore a set of files to a previous state and are essentially faster, safer ways of undoing mistakes than using the p4 obliterate command (and you don't need admin access to use them).
In the case of "Rollback...", this could be any number of files, even an entire...
How can I keep Bootstrap popovers alive while being hovered?
I am using a Bootstrap popover to create a hover card showing user info, and I am triggering it on mouseover of a button. I want to keep this popover alive while the popover itself is being hovered, but it disappears as soon as the user stops hovering over the button. How can I do this?
...
Difference between 'struct' and 'typedef struct' in C++?
... It's a holdover from C, in which it makes a difference.
The C language standard (C89 §3.1.2.3, C99 §6.2.3, and C11 §6.2.3) mandates separate namespaces for different categories of identifiers, including tag identifiers (for struct/union/enum) and ordinary identifiers (for typedef and other iden...