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Difference between left join and right join in SQL Server [duplicate]
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@SilapAliyev That's actually a very good question. Can anyone answer? :D
– Ian Chu Te
Jan 8 '16 at 2:46
21
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计算统计特征（正态分布）函数及实例 - C/C++ - 清泛网 - 专注C/C++及内核技术
...AX_VAR;
double _ave;
//double _var;
double _sam_stdev;
double _all_stdev;
double _sum;
double _sum_2;
int _count;
double _min_v;
double _max_v;
StdevInfo()
: _ave(0.0)
//, _var(MAX_VAR)
, _sam_stdev(sqrt(MAX_VAR))
, _all_stdev(0.0)
, _sum(0.0)
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How to load all modules in a folder?
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List all python (.py) files in the current folder and put them as __all__ variable in __init__.py
from os.path import dirname, basename, isfile, join
import glob
modules = glob.glob(join(dirname(__file__), "*.py"))
__all__ = [ ba...
Detect backspace in empty UITextField
...yTextField
- (void)deleteBackward {
[super deleteBackward];
if ([_myDelegate respondsToSelector:@selector(textFieldDidDelete)]){
[_myDelegate textFieldDidDelete];
}
}
@end
Now simply add MyTextFieldDelegate to your UIViewController and set your UITextFields myDelegate to sel...
Compression/Decompression string with C#
...not be written to the output stream until the GZipStream knows that it has all of the input (i.e., to effectively compress it needs all of the data). You need to make sure that you Dispose() of the GZipStream before inspecting the output stream (e.g., mso.ToArray()). This is done with the using() { ...
How to compare times in Python?
...use for comparison without taking the date into account:
>>> this_morning = datetime.datetime(2009, 12, 2, 9, 30)
>>> last_night = datetime.datetime(2009, 12, 1, 20, 0)
>>> this_morning.time() < last_night.time()
True
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How to sort a Ruby Hash by number value?
...ea.com" => 745, "siteb.com" => 9, "sitec.com" => 10 }
metrics.sort_by {|_key, value| value}
# ==> [["siteb.com", 9], ["sitec.com", 10], ["sitea.com", 745]]
If you need a hash as a result, you can use to_h (in Ruby 2.0+)
metrics.sort_by {|_key, value| value}.to_h
# ==> {"siteb.c...
PSQLException: current transaction is aborted, commands ignored until end of transaction block
...gnored as a failed SQL statement. You are welcome to fail SQL statements all you want and PostgreSQL won't stop you.
Stay being in a transaction, but when you detect that the first SQL has failed, either rollback/re-start or commit/restart the transaction. Then you can continue failing as many S...
Java: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification
...ur browser and add it to cacerts file of your JVM. You can either edit JAVA_HOME/jre/lib/security/cacerts file or run you application with -Djavax.net.ssl.trustStore parameter. Verify which JDK/JRE you are using too as this is often a source of confusion.
See also: How are SSL certificate server na...
IntelliJ not recognizing a particular file correctly, instead its stuck as a text file
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This worked for me, must have somehow accidentally added my filename.
– Harrison
Oct 7 '15 at 18:22
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