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When should a class be Comparable and/or Comparator?
I have seen classes which implement both Comparable and Comparator . What does this mean? Why would I use one over the other?
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Adding an identity to an existing column
I need to change the primary key of a table to an identity column, and there's already a number of rows in table.
19 Answe...
Using HTML5/JavaScript to generate and save a file
I've been fiddling with WebGL lately, and have gotten a Collada reader working. Problem is it's pretty slow (Collada is a very verbose format), so I'm going to start converting files to a easier to use format (probably JSON). I already have the code to parse the file in JavaScript, so I may as well ...
How to delete duplicates on a MySQL table?
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Notice: this would keep the oldest duplicate record and would erase the newer ones. If you want to keep the newest you cannot do this with ALTER IGNORE.
– Haralan Dobrev
Oct 1 '12 at 10:26
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How to upgrade PostgreSQL from version 9.6 to version 10.1 without losing data?
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Assuming you've used home-brew to install and upgrade Postgres, you can perform the following steps.
Stop current Postgres server:
launchctl unload ~/Library/LaunchAgents/homebrew.mxcl.postgresql.plist
Initialize a new 10.1 database:
initdb /usr/local/var/postgre...
Service vs IntentService in the Android platform
... can be done with an IntentService that cannot be done with a Service (and vice-versa)?
11 Answers
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Why can't I reference my class library?
I have a solution that contains a website and a class library in Visual Studio 2008.
20 Answers
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What does “var FOO = FOO || {}” (assign a variable or an empty object to that variable) mean in Java
...s is used to create a namespace, i.e. a named object under which functions and variables can be created without unduly polluting the global object.
The reason why it's used is so that if you have two (or more) files:
var MY_NAMESPACE = MY_NAMESPACE || {};
MY_NAMESPACE.func1 = {
}
and
var MY_NAM...
How to find all positions of the maximum value in a list?
... 0 for this is 2n, the list is iterated through 2x, once to determine max, and another time to find the positions of the max. A for loop that tracks the current max and its position might be more efficient for really long lists.
– radtek
Jan 8 '15 at 18:42
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Clear terminal in Python [duplicate]
Does any standard "comes with batteries" method exist to clear the terminal screen from a Python script, or do I have to go curses (the libraries, not the words)?
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