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Difference between a theta join, equijoin and natural join
I'm having trouble understanding relational algebra when it comes to theta joins, equijoins and natural joins. Could someone please help me better understand it? If I use the = sign on a theta join is it exactly the same as just using a natural join?
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Auto margins don't center image in page
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add display:block; and it'll work. Images are inline by default
To clarify, the default width for a block element is auto, which of course fills the entire available width of the containing element.
By setting the margin to auto, the browser ...
Master-master vs master-slave database architecture?
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We're trading off availability, consistency and complexity. To address the last question first: Does this matter? Yes very much! The choices concerning how your data is to be managed is absolutely fundamental, and there's no "Best Practice" dodging the decisions. You n...
What exactly do the Vagrant commands do?
There is surprisingly no documentation on what the Vagrant commands do, other than references throughout the "getting started" tutorial.
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Python division
...s trying to normalize a set of numbers from -100 to 0 to a range of 10-100 and was having problems only to notice that even with no variables at all, this does not evaluate the way I would expect it to:
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What is the difference between attribute and property? [closed]
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In general terms (and in normal English usage) the terms mean the same thing.
In the specific context of HTML / Javascript the terms get confused because the HTML representation of a DOM element has attributes (that being the term used in XML...
.NET unique object identifier
...ing (GUID, integer, whatever). That would add a certain amount of overhead and complexity, however.
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Determine if code is running as part of a unit test
...n. It only needed to do this once, then cache the result. Ugly, but simple and effective.
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Android Left to Right slide animation
...e launch modes are single instance.
Using onfling() , I swing them left and right.
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Python: json.loads returns items prefixing with 'u'
I'll be receiving a JSON encoded string form Obj-C, and I am decoding a dummy string (for now) like the code below. My output comes out with character 'u' prefixing each item:
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