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Is there a REAL performance difference between INT and VARCHAR primary keys?
... and a coworker won't budge on the INT AUTO_INCREMENT as a primary key for all tables.
14 Answers
...
Performing Inserts and Updates with Dapper
...Connection extension methods:
T Get<T>(id);
IEnumerable<T> GetAll<T>();
int Insert<T>(T obj);
int Insert<T>(Enumerable<T> list);
bool Update<T>(T obj);
bool Update<T>(Enumerable<T> list);
bool Delete<T>(T obj);
bool Delete<T>(Enumera...
Installing older version of R package
...
To install an older version of a package from source (within R):
packageurl <- "http://cran.r-project.org/src/contrib/Archive/ggplot2/ggplot2_0.9.1.tar.gz"
install.packages(packageurl, repos=NULL, type="source")
If this doesn'...
Visual Studio debugging/loading very slow
I'm at wits end. Visual Studio is typically painfully slow to debug or just plain load ("start without debugging") my ASP.NET MVC sites. Not always: at first, the projects will load nice and fast, but once they load slow, they'll always load slow after that. I could be waiting 1-2 minutes or more....
What is the difference between .*? and .* regular expressions?
...nsider the input 101000000000100.
Using 1.*1, * is greedy - it will match all the way to the end, and then backtrack until it can match 1, leaving you with 1010000000001.
.*? is non-greedy. * will match nothing, but then will try to match extra characters until it matches 1, eventually matching 101...
ASP.NET WebApi vs MVC ? [closed]
...
WebApi allows to create services that can be exposed over HTTP rather than through a formal service such as WCF or SOAP.
Another difference is in the way how WebApi uses Http protocol and makes it truly First class Http citizen.
U...
Using semicolon (;) vs plus (+) with exec in find
...mand line length. If the command exceeds this length, the command will be called multiple times.
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PHP global in functions
...ngletons, registries, constants). You do not want to use them. A function call should not have to rely on anything outside, e.g.
function fn()
{
global $foo; // never ever use that
$a = SOME_CONSTANT // do not use that
$b = Foo::SOME_CONSTANT; // do not use that unl...
Is it better to use Enumerable.Empty() as opposed to new List() to initialize an IEnumerable
...uld be noticeable impact.
Enumerable.Empty does not create an object per call thus putting less load on GC.
If the code is in low-throughput location, then it boils down to aesthetic considerations though.
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adding x and y axis labels in ggplot2
...+
ylab("My y label") +
ggtitle("Weighted Scatterplot of Watershed Area vs. Discharge and Nitrogen Levels (PPM)")
ggplot(ex1221, aes(Discharge, Area)) +
geom_point(aes(size=NO3)) +
scale_size_area("Nitrogen") +
scale_x_continuous("My x label") +
scale_y_continuous("My y label") +
...