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Cannot use identity column key generation with ( TABLE_PER_CLASS )
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The problem here is that you mix "table-per-class" inheritance and GenerationType.Auto.
Consider an identity column in MsSQL. It is column based. In a "table-per-class" strategy you use one table per class and each one has an ID.
Try:
@GeneratedValue(strategy = GenerationType.TABLE)
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How to log cron jobs?
...og/myjob.log
You might use mail to send emails. Most systems will send unhandled cron job output by email to root or the corresponding user.
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PHP 5 disable strict standards error
... to setup my PHP script at the top to disable error reporting for strict standards.
7 Answers
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How to serialize SqlAlchemy result to JSON?
... {}
for field in [x for x in dir(obj) if not x.startswith('_') and x != 'metadata']:
data = obj.__getattribute__(field)
try:
json.dumps(data) # this will fail on non-encodable values, like other classes
fields[field]...
Best practice to validate null and empty collection in Java
I want to verify whether a collection is empty and null . Could anyone please let me know the best practice.
9 Answers
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Getting started with F# [closed]
...t). (contains interactive tutorial walkthroughs)
Start by watching videos and presentations (BTW, An Introduction to Microsoft F# by Luca Bolognese is still one of the best presentations on the subject). Then read the following two must-read books:
Programming F#: A comprehensive guide for writin...
What do *args and **kwargs mean? [duplicate]
What exactly do *args and **kwargs mean?
5 Answers
5
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Switch statement: must default be the last case?
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The C99 standard is not explicit about this, but taking all facts together, it is perfectly valid.
A case and default label are equivalent to a goto label. See 6.8.1 Labeled statements. Especially interesting is 6.8.1.4, which enables...
What is so bad about singletons? [closed]
.... I still use quite a lot of singletons, especially for factory classes , and while you have to be a bit careful about multithreading issues (like any class actually), I fail to see why they are so awful.
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How to convert a scala.List to a java.util.List?
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Scala List and Java List are two different beasts, because the former is immutable and the latter is mutable. So, to get from one to another, you first have to convert the Scala List into a mutable collection.
On Scala 2.7:
import sca...