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Which data type for latitude and longitude?
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If you do not need all the functionality PostGIS offers, Postgres (nowadays) offers an extension module called earthdistance. It uses the point or cube data type depending on your accuracy needs for distance calculations.
You can now use the earth_box function to -for example- query for poi...
Deploying my application at the root in Tomcat
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I know that my answer is kind of overlapping with some of the other answer, but this is a complete solution that has some advantages. This works on Tomcat 8:
The main application is served from the root
The deployment of war f...
MySql: Tinyint (2) vs tinyint(1) - what is the difference?
.... This kind of feature made some sense in the early days of databases, but now it is just legacy.
– Denilson Sá Maia
Aug 28 '14 at 20:03
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How can I get a precise time, for example in milliseconds in Objective-C?
...liseconds
// Use (-) modifier to conversion since receiver is earlier than now
double timePassed_ms = [date timeIntervalSinceNow] * -1000.0;
Documentation on timeIntervalSinceNow.
There are many other ways to calculate this interval using NSDate, and I would recommend looking at the class documen...
How to automatically convert strongly typed enum into int?
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That's another weird example of 'we know better what you want to do' from C++ creators. Conventional (old-style) enums had tons of benefits like implicit conversion to indexes, seamless using of bitwise operations etc.. The new style enums added a really great ...
What is the fastest way to get the value of π?
...ll depends on what kind of accuracy you are looking for. The fastest π I know of is the one with the digits hard coded. Looking at Pi and Pi[PDF], there are a lot of formulae.
Here is a method that converges quickly — about 14 digits per iteration. PiFast, the current fastest application, uses t...
SQL Server dynamic PIVOT query?
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Cool! Do you know of a way to add a prefix to the value column names - so you have a result with columns: date, Amount_ABC, Amount_DEF, Amount_GHI? I am asking, because I would like to join an additional value column to it and then I would...
Decode Base64 data in Java
...Who knew this would be the most controversial answer I'd ever post? I do know that sun.* packages are not supported or guaranteed to continue existing, and I do know about Commons and use it all the time. However, the poster asked for a class that that was "included with Sun Java 6," and that's wh...
How to iterate over associative arrays in Bash
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This is now if assign all keys to an array: array=(${!hash[@]})
– Michael-O
Jun 6 '13 at 10:54
12
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Start may not be called on a promise-style task. exception is coming
...ask.Run or Task.Factory.StartNew to both create and start a new Task.
So, now we know to just get rid of that pesky Start. You'll run your code and find that the message box is shown right away, not 5 seconds later, what's up with that?
Well, Task.Delay just gives you a task that will be complete...