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How to tell if a string is not defined in a Bash shell script
...Autoconf, you'll find that they do not recommend combining terms with '-a' and do recommend using separate simple tests combined with &&. I've not encountered a system where there is a problem; that doesn't mean they didn't used to exist (but they are probably extremely rare these days, eve...
Java compiler level does not match the version of the installed Java project facet
...you are using the m2e plugin in Eclipse, you'll need to specify the source and target versions as 1.6 for maven-compiler-plugin. m2e uses these values to determine the project's Java compiler level. A snippet of the POM is shown below:
<build>
<plugins>
<plugin>
<ar...
How does the const constructor actually work?
...calized" instance.
That is, all constant expressions begin canonicalized, and later these "canonicalized" symbols are used to recognize equivalence of these constants.
Canonicalization:
A process for converting data that has more than one possible representation into a "standard" canonical repres...
How do CDI and EJB compare? interact?
I'm having a tough time understanding how the two interact and where the boundary between them lies. Do they overlap? Are there redundancies between them?
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How to build an android library with Android Studio and gradle?
...lipse but nothing I have tried is working. In Eclipse I have 3 projects (2 android app projects and 1 android library project). The 2 app projects depend on the library project. When I do the gradle export I get 3 projects that don't work. I am open to restructuring the project but haven't found any...
How to create a directory if it doesn't exist using Node.js?
...rectory if it doesn't exist.
It should have full permission for the script and readable by others.
17 Answers
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Copy a table from one database to another in Postgres
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Extract the table and pipe it directly to the target database:
pg_dump -t table_to_copy source_db | psql target_db
Note: If the other database already has the table set up, you should use the -a flag to import data only, else you may see we...
Explicitly calling return in a function or not
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Question was: Why is not (explicitly) calling return faster or better, and thus preferable?
There is no statement in R documentation making such an assumption.
The main page ?'function' says:
function( arglist ) expr
return(value)
Is it faster without calling return?
Both function() and re...
How to generate a range of numbers between two numbers?
I have two numbers as input from the user, like for example 1000 and 1050 .
28 Answers
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How can we make xkcd style graphs?
...ly, folk have figured out how to make xkcd style graphs in Mathematica and in LaTeX . Can we do it in R? Ggplot2-ers? A geom_xkcd and/or theme_xkcd?
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