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When do I need to use a semicolon vs a slash in Oracle SQL?
We have been having some debate this week at my company as to how we should write our SQL scripts.
6 Answers
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using gitignore to ignore (but not delete) files
I have a tmp directory in my git repo I'd like to still exist, but be ignored. I added it to .gitignore , but git status still tells me about changes to files in that directory. I tried git rm -r --cached , but that removes it from the remote repo. How can I stop tracking changes to this dire...
What's the difference between an exclusive lock and a shared lock?
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I wrote this answer down because I thought this would be a fun (and fitting) analogy:
Think of a lockable object as a blackboard (lockable) in a class room containing a teacher (writer) and many students (readers).
While a teacher is writing something ...
Difference between size_t and std::size_t
...ize_t and std::size_t in terms of where they are declared, when they should be used and any other differentiating features?
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What's the longest possible worldwide phone number I should consider in SQL varchar(length) for phon
What's the longest possible worldwide phone number I should consider in SQL varchar(length) for phone.
5 Answers
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What is the purpose of AsQueryable()?
Is the purpose of AsQueryable() just so you can pass around an IEnumerable to methods that might expect IQueryable , or is there a useful reason to represent IEnumerable as IQueryable ? For example, is it supposed to be for cases like this:
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font-style: italic vs oblique in CSS
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In the purest (type designer) sense, an oblique is a roman font that has been skewed a certain number of degrees (8-12 degrees, usually). An italic is created by the type designer with specific characters (notably lowercase a) drawn ...
Why doesn't the JVM cache JIT compiled code?
The canonical JVM implementation from Sun applies some pretty sophisticated optimization to bytecode to obtain near-native execution speeds after the code has been run a few times.
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Why JSF saves the state of UI components on server?
Now, it is no longer necessary to save state while using JSF. A high performance Stateless JSF implementation is available for use. See this blog & this question for relevant details & discussion. Also, there is an open issue to include in JSF specs, an option to provide stateless mode for JSF...
Does MySQL ignore null values on unique constraints?
I have an email column that I want to be unique. But I also want it to accept null values. Can my database have 2 null emails that way?
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