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MySQL: selecting rows where a column is null

... NULL = NULL is not really FALSE - it's NULL again. But it's not TRUE either, so IF(NULL = NULL) won't execute. – Konerak Jan 12 '11 at 19:50 ...
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Center HTML Input Text Field Placeholder

... input{ text-align:center; } is all you need. Working example in FF6. This method doesn't seem to be cross-browser compatible. Your previous CSS was attempting to center the text of an input element which had a class of "placeholder". ...
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Why use Ruby instead of Smalltalk? [closed]

...hrough its adolescence. There are a lot of similarities between Ruby and Smalltalk -- maglev is a testament to that. Despite having a more unusual syntax, Smalltalk has all (if not more) of the object-oriented beauty of Ruby. ...
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How to hide TabPage from TabControl [duplicate]

... But RemoveByKey() + Add() is totally working – Vinko Vrsalovic Oct 3 '13 at 14:30 3 ...
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Taking screenshot on Emulator from Android Studio

...when I changed the default Desktop location to my Pictures library. Before all looked fine, but it didn't save the screenshot – lvmeijer Feb 11 '19 at 2:30 add a comment ...
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Declaring and initializing variables within Java switches

... Switch statements are odd in terms of scoping, basically. From section 6.3 of the JLS: The scope of a local variable declaration in a block (§14.4) is the rest of the block in which the declaration appears, starting with its own initializer and including any further decla...
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How to determine the number of days in a month in SQL Server?

... All of the solutions mentioned here pale in comparison to the elegance of @Mikael Eriksson's answer. That works whenever a valid date is provided without crazy workarounds for niche cases and is far simpler code - I'd highly...
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Converting 'ArrayList to 'String[]' in Java

...you can also pass an array with the desired size. Important update: Originally the code above used new String[list.size()]. However, this blogpost reveals that due to JVM optimizations, using new String[0] is better now. sh...
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How to calculate the bounding box for a given lat/lng location?

... I suggest to approximate locally the Earth surface as a sphere with radius given by the WGS84 ellipsoid at the given latitude. I suspect that the exact computation of latMin and latMax would require elliptic functions and would not yield an appreciable ...
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When should you NOT use a Rules Engine? [closed]

...hat conflicts don't exist. I think partitioning rules sets to keep them small is a better option. Aspects can be a way to share a common rule set among many objects. I prefer a simpler, more data driven approach wherever possible. ...