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PostgreSQL delete with inner join
...ered Jul 30 '15 at 18:41
Robert CaseyRobert Casey
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pandas resample documentation
...frequency
C custom business day frequency (experimental)
D calendar day frequency
W weekly frequency
M month end frequency
SM semi-month end frequency (15th and end of month)
BM business month end frequency
CBM custom business month end frequency
M...
What is the difference between Collections.emptyList() and Collections.EMPTY_LIST
...t is probably always preferable. This way, you don't need to unnecessarily cast around within your code.
Collections.emptyList() intrinsically does the cast for you.
@SuppressWarnings("unchecked")
public static final <T> List<T> emptyList() {
return (List<T>) EMPTY_LIST;
}
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What is the use of the pipe symbol in YAML?
...that any indented text that follows should be interpreted as a multi-line scalar value. See the YAML spec.
Specifically, the pipe indicates that (except for the indentation) the scalar value should be interpreted literally in such a way that preserves newlines. Conversely, the > character indi...
How to deal with “data of class uneval” error from ggplot2?
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Another cause is accidentally putting the data=... inside the aes(...) instead of outside:
RIGHT:
ggplot(data=df[df$var7=='9-06',], aes(x=lifetime,y=rep_rate,group=mdcp,color=mdcp) ...)
WRONG:
ggplot(aes(data=df[df$var7=='9-06',],x...
Groovy / grails how to determine a data type?
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To determine the class of an object simply call:
someObject.getClass()
You can abbreviate this to someObject.class in most cases. However, if you use this on a Map it will try to retrieve the value with key 'class'. Because of this, I always use getClass() even tho...
Printing newlines with print() in R
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An alternative to cat() is writeLines():
> writeLines("File not supplied.\nUsage: ./program F=filename")
File not supplied.
Usage: ./program F=filename
>
An advantage is that you don't have to remember to append a "\n" to the string p...
Visual studio long compilation when replacing int with double
... the Windows Defender service, the one that actually performs the malware scans. Disabling it by unticking the "Turn on real-time protection" option instantly fixes the delay. So does adding the path where I store projects to the "Excluded file locations" box, probably your preferred approach.
I'...
How to put comments in Django templates
... {% comment %}...{% endcomment %} is used for multi-line comments, but you can also comment out text on the same line like this:
{# some text #}
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optional parameters in SQL Server stored proc?
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You can declare like this
CREATE PROCEDURE MyProcName
@Parameter1 INT = 1,
@Parameter2 VARCHAR (100) = 'StringValue',
@Parameter3 VARCHAR (100) = NULL
AS
/* check for the NULL / default value (indicating nothing was...