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Checking for an empty field with MySQL
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An empty field can be either an empty string or a NULL.
To handle both, use:
email > ''
which can benefit from the range access if you have lots of empty email record (both types) in your table.
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Does a javascript if statement with multiple conditions test all of them?
...IT: Though, you shouldn't worry about performance until you've benchmarked and determined that it's a problem. Premature micro-optimization is the bane of maintainability.
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ALTER TABLE without locking the table?
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And have a thorough test plan before swapping. If it fails, start over.
– dkretz
Jan 21 '09 at 2:29
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Maven: The packaging for this project did not assign a file to the build artifact
I'm using Maven 3.0.3 on Mac 10.6.6. I have a JAR project and when I run the command "mvn clean install:install", I'm getting the error,
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How can I unit test Arduino code?
...Sim-based tests
There's a lot of discussion about what unit test means and I'm not
really trying to make an argument about that here. This post is not
telling you to avoid all practical testing on your ultimate target
hardware. I am trying to make a point about optimizing your
developmen...
How do I convert an integer to binary in JavaScript?
...nswered Apr 22 '13 at 19:43
fernandosaviofernandosavio
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Position Relative vs Absolute?
What is the difference between position: relative and position: absolute in CSS? And when should you use them?
10 Answe...
How much faster is Redis than mongoDB?
It's widely mentioned that Redis is "Blazing Fast" and mongoDB is fast too. But, I'm having trouble finding actual numbers comparing the results of the two. Given similar configurations, features and operations (and maybe showing how the factor changes with different configurations and operations), ...
Difference between numpy.array shape (R, 1) and (R,)
...ning of shapes in NumPy
You write, "I know literally it's list of numbers and list of lists where all list contains only a number" but that's a bit of an unhelpful way to think about it.
The best way to think about NumPy arrays is that they consist of two parts, a data buffer which is just a block...
Setting DIV width and height in JavaScript
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The properties you're using may not work in Firefox, Chrome, and other non-IE browsers. To make this work in all browsers, I also suggest adding the following:
document.getElementById('div_register').setAttribute("style","width:500px");
For cross-compatibility, you will still need t...