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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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Why are unnamed namespaces used and what are their benefits?
I just joined a new C++ software project and I'm trying to understand the design. The project makes frequent use of unnamed namespaces. For example, something like this may occur in a class definition file:
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What is the best Java email address validation method? [closed]
...verification email to the address if you want to ensure it's a real email, and that the owner wants it used on your site.
EDIT: There was a bug where it was too restrictive on domain, causing it to not accept valid emails from new TLDs.
This bug was resolved on 03/Jan/15 02:48 in commons-validator ...
Unit Testing AngularJS directive with templateUrl
... ngMock. The ngMock module is automatically loaded for every Angular test, and it initializes the mock $httpBackend to handle any use of the $http service, which includes template fetching. The template system tries to load the template through $http and it becomes an "unexpected request" to the moc...
Auto Resize Image in CSS FlexBox Layout and keeping Aspect Ratio?
...oking for an answer to my distorted images" i got here for the same reason and your solution helped me (what was marked as the actual solution didn't help me at all)
– Wagner Danda da Silva Filho
Jun 29 '16 at 17:30
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Amazon Interview Question: Design an OO parking lot [closed]
Design an OO parking lot. What classes and functions will it have. It should say, full, empty and also be able to find spot for Valet parking. The lot has 3 different types of parking: regular, handicapped and compact.
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How to tell if a string is not defined in a Bash shell script
...Autoconf, you'll find that they do not recommend combining terms with '-a' and do recommend using separate simple tests combined with &&. I've not encountered a system where there is a problem; that doesn't mean they didn't used to exist (but they are probably extremely rare these days, eve...
.classpath and .project - check into version control or not?
...recent Eclipse3.5 settings, where build paths support relative paths:
And Eclipse3.6 would be better, as it supports relative paths for path variables in Linked Resources:
(since 3.6M5)
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Do the JSON keys have to be surrounded by quotes?
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Yes, you need quotation marks. This is to make it simpler and to avoid having to have another escape method for javascript reserved keywords, ie {for:"foo"}.
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getViewTypeCount and getItemViewType methods of ArrayAdapter
Can somebody in plain words explain me the usage of getViewTypeCount() and getItemViewType() methods of ArrayAdapter ?
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