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What is Normalisation (or Normalization)?
...Normalization is basically to design a database schema such that duplicate and redundant data is avoided. If some piece of data is duplicated several places in the database, there is the risk that it is updated in one place but not the other, leading to data corruption.
There is a number of normal...
How do I interpret precision and scale of a number in a database?
...rget that if you're using a system that allows you to pre-define precision and scale of an input for a percentage in something like Microsoft Access, you must consider the percent as it's whole number form. In this case, 25.5% would require precision 4 and scale of 3 (not one) since we have to cons...
Changing Ctrl + Tab behavior for moving between documents in Visual Studio
Is it possible to change how Ctrl + Tab and Shift + Ctrl + Tab work in Visual Studio? I have disabled the popup navigator window, because I only want to switch between items in the tab control. My problem is the inconsistency of what switching to the next and previous document do.
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Firing events on CSS class changes in jQuery
...that way, when the event is triggered, those events can all happen at once and run their respective functionality. for instance, if i have one object that changes from red to blue and three objects waiting for it to change, when it changes, i can just trigger the changeColor event, and all those obj...
java.lang.UnsupportedClassVersionError Unsupported major.minor version 51.0 [duplicate]
...ortedClassVersionError happens because of a higher JDK during compile time and lower JDK during runtime.
Here's the list of versions:
Java SE 9 = 53,
Java SE 8 = 52,
Java SE 7 = 51,
Java SE 6.0 = 50,
Java SE 5.0 = 49,
JDK 1.4 = 48,
JDK 1.3 = 47,
JDK 1.2 = 46,
JDK 1.1 = 45
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Cannot add or update a child row: a foreign key constraint fails
... not sure what the downvote is for; my answer is perfectly valid and correct.
– Brian Driscoll
Feb 15 '11 at 15:20
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Maven Install on Mac OS X
...X Lion, you won't have java installed by default. Just run java by itself and it'll prompt you to install it.
Assuming qualifications are met, run mvn -version and see some output like this:
Apache Maven 3.0.3 (r1075438; 2011-02-28 12:31:09-0500)
Maven home: /usr/share/maven
Java version: 1.6.0_2...
What XML parser should I use in C++? [closed]
I have XML documents that I need to parse and/or I need to build XML documents and write them to text (either files or memory). Since the C++ standard library does not have a library for this, what should I use?
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With bash, how can I pipe standard error into another process?
It's well known how to pipe the standard ouput of a process into another processes standard input:
5 Answers
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Preventing form resubmission
Page one contains an HTML form. Page two - the code that handles the submitted data.
12 Answers
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