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Oracle Differences between NVL and Coalesce
...ented differently.
NVL always evaluates both arguments, while COALESCE usually stops evaluation whenever it finds the first non-NULL (there are some exceptions, such as sequence NEXTVAL):
SELECT SUM(val)
FROM (
SELECT NVL(1, LENGTH(RAWTOHEX(SYS_GUID()))) AS val
FROM dual
...
R memory management / cannot allocate vector of size n Mb
...
Consider whether you really need all this data explicitly, or can the matrix be sparse? There is good support in R (see Matrix package for e.g.) for sparse matrices.
Keep all other processes and objects in R to a minimum when you need to make obj...
When should I use RequestFactory vs GWT-RPC?
I am trying to figure out if I should migrate my gwt-rpc calls to the new GWT2.1 RequestFactory cals.
8 Answers
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Conditionally use 32/64 bit reference when building in Visual Studio
...file(s). You also need separate directories for the different binaries, ideally siblings of each other, and with the same name as the platform you are targeting.
After adding a single platform's references to the project, open the .csproj in a text editor. Before the first <ItemGroup> element...
Test if something is not undefined in JavaScript
...eryone seems to think it is). If you want to, you could create a variable called undefined and then this check will be incorrect. The only correct way is to check (typeof myVar !== 'undefined').
– BadHorsie
Jun 20 '16 at 14:12
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Double vs single quotes
I'm really new to Ruby and I'm trying to understand if there's a specific time when I should use "" vs '' .
8 Answers
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Prevent flicker on webkit-transition of webkit-transform [duplicate]
...ing other elements on the site and I ended up by having to add the rule to all elements on the site.
– mlunoe
Jan 10 '13 at 13:53
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Why is “throws Exception” necessary when calling a function?
...he Throwable class. However, you don't need to specify a throws clause for all classes. Specifically, classes that are either an Error or RuntimeException or any of the subclasses of these two. In your case Exception is not a subclass of an Error or RuntimeException. So, it is a checked exception an...
Can Git hook scripts be managed along with the repository?
We'd like to make a few basic hook scripts that we can all share -- for things like pre-formatting commit messages. Git has hook scripts for that that are normally stored under <project>/.git/hooks/ . However, those scripts are not propagated when people do a clone and they are not version ...
Why does a base64 encoded string have an = sign at the end
...org/wiki/Base64#Output_padding is pretty good. But the answer by Badr is really a better one (it just hasn't caught up in votes yet).
– NH.
Jul 9 '19 at 18:58
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