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Bash continuation lines
... Thanks for your help, but while this does remove the spaces, they are now separate parameters (Bash is interpreting the spaces on the second line as a parameter separator) and are now only printed correctly because of the echo command.
– user880248
Sep 6 '...
JPA CascadeType.ALL does not delete orphans
... all child elements
delete main row
close session
With JPA 2.0, you can now use the option orphanRemoval = true
@OneToMany(mappedBy="foo", orphanRemoval=true)
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Generate random number between two numbers in JavaScript
...the equation, this is equivalent to
0 <= (X - min) <= (max - min)
Now, lets multiply this with a random number r
which is
0 <= (X - min) * r <= (max - min) * r
Now, lets add back min to the equation
min <= min + (X - min) * r <= min + (max - min) * r
Now, lets chose a funct...
Run PostgreSQL queries from the command line
I inserted a data into a table....I wanna see now whole table with rows and columns and data. How I can display it through command?
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Error: This Android SDK requires Android Developer Toolkit version 22.6.1 or above
...> add this url : https://dl-ssl.google.com/eclipse/plugin/4.2 -> OK
Now it will list the available updates, which should ideally be adt 20.x.x
Select the list items Let it be installed. Eclipse will restart and Its done.
I hope this will helpful for you :)
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How to add hours to current time in python
...
from datetime import datetime, timedelta
nine_hours_from_now = datetime.now() + timedelta(hours=9)
#datetime.datetime(2012, 12, 3, 23, 24, 31, 774118)
And then use string formatting to get the relevant pieces:
>>> '{:%H:%M:%S}'.format(nine_hours_from_now)
'23:24:31'
I...
NVIDIA vs AMD: GPGPU performance
... in scientific computing), tilt the balance in favor of CUDA (at least for now).
EDIT Jan 12, 2013
It's been two years since I made this post and it still seems to attract views sometimes. So I have decided to clarify a few things
AMD has stepped up their game. They now have both BLAS and FFT ...
how to emulate “insert ignore” and “on duplicate key update” (sql merge) with postgresql?
...rows and with mysql i can do this with only ONE query without any looping. Now I wonder if this is possible with postgresql too: to use just one query to bulk update OR insert. You say: "you're best of splitting it into two queries, one for INSERT and one for UPDATE" but how can I do an insert which...
How can I generate Unix timestamps?
...1970-01-01 00:00:00 UTC. (GNU Coreutils 8.24 Date manual)
Example output now 1454000043.
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Why does ('0' ? 'a' : 'b') behave different than ('0' == true ? 'a' : 'b') [duplicate]
...the empty String (its length is zero);
otherwise the result is true.
Now to '0' == true.
Two type conversions will take place here. We can follow this in the specification, section 11.9.3, The Abstract Equality Comparison Algorithm.
The operands are denoted as x and y (x == y).
In our case...