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Hibernate throws org.hibernate.AnnotationException: No identifier specified for entity: com..domain.
...d with @Id. Each @Entity needs an @Id - this is the primary key in the database.
If you don't want your entity to be persisted in a separate table, but rather be a part of other entities, you can use @Embeddable instead of @Entity.
If you want simply a data transfer object to hold some data from ...
Mvn install or Mvn package
I am new to Maven, I have a Java based web project with maven configured in my MyEclipse.
Now if I modified any java files then do I need to do Run as -> Mvn install or Mvn package ?
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Draw line in UIView
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Based on Guy Daher's answer.
I try to avoid using ? because it can cause an application crash if the GetCurrentContext() returns nil.
I would do nil check if statement:
class CustomView: UIView
{
override func dra...
My Understanding of HTTP Polling, Long Polling, HTTP Streaming and WebSockets
...nnections from clients puts more load on the server.
WebSockets are a TCP-based protocol and as such don't suffer from this HTTP-level connection limit (but, of course, browser support is not uniform).
share
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How to truncate the time on a DateTime object in Python?
...The advantage compared to the .replace() method is that datetime.combine()-based solution will continue to work even if datetime module introduces the nanoseconds support.
tzinfo can be preserved if necessary but the utc offset may be different at midnight e.g., due to a DST transition and therefor...
Why is === faster than == in PHP?
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@Marco, when I say "empirical study", I mean it's based on experience, eg: running code instead of making an argument using only reason (or what's in your mind), without an experiment to back it up. Salman A values suggest === is equally sometimes a bit faster and sometimes...
PostgreSQL “DESCRIBE TABLE”
...e.g. numeric(6,2); whereas information_schema.columns will only report the base type of numeric.
– Eli Collins
Dec 6 '14 at 2:26
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What is an .inc and why use it?
... make PHP parse read PHP code from it. Useful when you want to create file based database and want to tell if it's a database file. like .data. You can then use @ClearCrescendo's comment above to secure it.
– Jomar Sevillejo
Dec 8 '15 at 11:28
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Numbering rows within groups in a data frame
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For making this r-faq question more complete, a base R alternative with sequence and rle:
df$num <- sequence(rle(df$cat)$lengths)
which gives the intended result:
> df
cat val num
4 aaa 0.05638315 1
2 aaa 0.25767250 2
1 aaa 0.30776611 3
5 aaa...
How to get a variable value if variable name is stored as string?
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Based on the answer: https://unix.stackexchange.com/a/111627
###############################################################################
# Summary: Returns the value of a variable given it's name as a string.
# Required ...