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MySQL: Insert record if not exists in table
...y suggesting that you do this, as the UNIQUE index as suggested by Piskvor and others is a far better way to do it, but you can actually do what you were attempting:
CREATE TABLE `table_listnames` (
`id` int(11) NOT NULL auto_increment,
`name` varchar(255) NOT NULL,
`address` varchar(255) NOT...
How to use arguments from previous command?
I know that Esc + . gives you the last argument of the last command.
11 Answers
11...
Easiest way to check for an index or a key in an array?
...
To check if the element is set (applies to both indexed and associative array)
[ ${array[key]+abc} ] && echo "exists"
Basically what ${array[key]+abc} does is
if array[key] is set, return abc
if array[key] is not set, return nothing
References:
See Parameter Expa...
What does the 'standalone' directive mean in XML?
What does the ' standalone ' directive mean in an XML document?
5 Answers
5
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Testing modules in rspec
...ting modules in rspec? I have some modules that get included in few models and for now I simply have duplicate tests for each model (with few differences). Is there a way to DRY it up?
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How can I configure Logback to log different levels for a logger to different destinations?
... things with Logback filters. The below configuration will only print warn and error messages to stderr, and everything else to stdout.
logback.xml
<appender name="stdout" class="ch.qos.logback.core.ConsoleAppender">
<target>System.out</target>
<filter class="com.foo.StdOu...
Do C# Timers elapse on a separate thread?
... The System.Threading.Timer class makes
callbacks on a ThreadPool thread and
does not use the event model at all.
So indeed the timer elapses on a different thread.
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Definition of a Balanced Tree
... tree for me. I have that "a tree is balanced if each sub-tree is balanced and the height of the two sub-trees differ by at most one.
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How to manage startActivityForResult on Android?
...ctivity,so you can set the result as "RESULT_CANCELLED" in the catch block and return to FirstActivty and in FirstActivity's' 'onActivityResult() you can check whether you got the success or failure result.
– Nishant
Oct 31 '13 at 4:42
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How do I access the $scope variable in browser's console using AngularJS?
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Pick an element in the HTML panel of the developer tools and type this in the console:
angular.element($0).scope()
In WebKit and Firefox, $0 is a reference to the selected DOM node in the elements tab, so by doing this you get the selected DOM node scope printed out in the conso...