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PostgreSQL: Can you create an index in the CREATE TABLE definition?
...BLE syntax. PostgreSQL does however create an index for unique constraints and primary keys by default, as described in this note:
PostgreSQL automatically creates an index for each unique constraint and primary key constraint to enforce uniqueness.
Other than that, if you want a non-unique in...
MySQL: how to get the difference between two timestamps in seconds
...nd the expression.
Alternatively, you can use TIMEDIFF(ts1, ts2) and then convert the time result to seconds with TIME_TO_SEC().
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Focusable EditText inside ListView
I've spent about 6 hours on this so far, and been hitting nothing but roadblocks. The general premise is that there is some row in a ListView (whether it's generated by the adapter, or added as a header view) that contains an EditText widget and a Button . All I want to do is be able to use t...
Getting All Variables In Scope
...ion:
var f = function() {
var x = 0;
console.log(x);
};
You can convert your function to a string:
var s = f + '';
You will get source of function as a string
'function () {\nvar x = 0;\nconsole.log(x);\n}'
Now you can use a parser like esprima to parse function code and find local ...
What is the difference between JVM, JDK, JRE & OpenJDK?
...exe), Java application launcher (java.exe), Appletviewer, etc…
Compiler converts java code into byte code. Java application launcher opens a JRE, loads the class, and invokes its main method.
You need JDK, if at all you want to write your own programs, and to compile them. For running java progr...
Can't specify the 'async' modifier on the 'Main' method of a console app
...) in VS2010 with the Async CTP.
I have recent blog posts about async/await and asynchronous console programs in particular. Here's some background info from the intro post:
If "await" sees that the awaitable has not completed, then it acts asynchronously. It tells the awaitable to run the remainder...
onCreateOptionsMenu inside Fragments
...nu.menu_sample, menu);
super.onCreateOptionsMenu(menu,inflater);
}
And in onCreate add this line to make the options appear in your Toolbar
setHasOptionsMenu(true);
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What is causing the error `string.split is not a function`?
...
Thank you. I didn't realized I converted my var from string to object. Your solution gave me an idea to check back my code.
– sg552
Nov 16 '16 at 16:53
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How to update maven repository in Eclipse?
...ies
After "BUILD SUCCESS", Right-click on your project then Configure > Convert Maven Project
Note: Maven update snapshot sometimes stops working if you use anything else i.e. eclipse:eclipse or Spring Tooling
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How to join (merge) data frames (inner, outer, left, right)
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Why do you need to convert CustomerId to numeric? I don't see any mentioning in documentation (for both plyr and dplyr) about this type of restriction. Would your code work incorrectly, if the merge column would be of character type (especially...