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Select rows which are not present in other table
...nated unless EXCEPT ALL is used.
Typically, you'll want the ALL keyword. If you don't care, still use it because it makes the query faster.
NOT IN
Only good without NULL values or if you know to handle NULL properly. I would not use it for this purpose. Also, performance can deteriorate with big...
docker error: /var/run/docker.sock: no such file or directory
... daemon, please set:
export DOCKER_CERT_PATH=
export DOCKER_TLS_VERIFY=1
export DOCKER_HOST=tcp://:2376
After setting these environment variables I was able to run the build without the problem.
Update [2016-04-28] If you are using a the recent versions of docker you can do
eval $(d...
Can I make a pull request on a gist on GitHub?
...ges in the fork, then share a link to your fork with the original author.
If the original author is keeping a local cloned repository of their gist (see How do you manage your gists on github?) then they can do a pull against your fork as a remote using the gist # (e.g. git://gist.github.com/113127...
Remove NA values from a vector
...st what you're asking for:
d <- c(1, 100, NA, 10)
max(d, na.rm=TRUE)
If you do want to remove all of the NAs, use this idiom instead:
d <- d[!is.na(d)]
A final note: Other functions (e.g. table(), lm(), and sort()) have NA-related arguments that use different names (and offer different o...
Create a custom View by inflating a layout?
...s so a custom layout is a custom view. Just something to consider because if you wanted to create a custom layout you could.
What you want to do is create a Compound Control. You'll create a subclass of RelativeLayout, add all our your components in code (TextView, etc), and in your constructor y...
Using multiple property files (via PropertyPlaceholderConfigurer) in multiple projects/modules
...
If you ensure that every place holder, in each of the contexts involved, is ignoring unresolvable keys then both of these approaches work. For example:
<context:property-placeholder
location="classpath:dao.properties,
...
Unsigned keyword in C++
Does the unsigned keyword default to a specific data type in C++? I am trying to write a function for a class for the prototype:
...
Javascript add leading zeroes to date
... and just ask for the last two since those are always the two we want.
So if the MyDate.getMonth() returns 9, it will be:
("0" + "9") // Giving us "09"
so adding .slice(-2) on that gives us the last two characters which is:
("0" + "9").slice(-2)
"09"
But if MyDate.getMonth() returns 10, it wi...
NULL vs nil in Objective-C
...hange:context: - why do the docs use NULL instead of nil when not specifying a context pointer?
5 Answers
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What are the best Haskell libraries to operationalize a program? [closed]
If I'm going to put a program into production, there are several things I need that program to do in order to consider it "operationalized" – that is, running and maintainable in a measurable and verifiable way by both engineers and operations staff. For my purposes, an operationalized program mus...