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Should I commit or rollback a read transaction?
I have a read query that I execute within a transaction so that I can specify the isolation level. Once the query is complete, what should I do?
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NoSQL Use Case Scenarios or WHEN to use NoSQL [closed]
...tion on when to use this. So I pose the following questions, and I'm sorry if these are really dumb questions in advance:
2...
_=> what does this underscore mean in Lambda expressions?
...same thing as in this example, even though _ has absolutely no special significance in Ruby.
– Jörg W Mittag
May 6 '10 at 5:33
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How do I fix "The expression of type List needs unchecked conversion…'?
...ast up front, you're "complying with the warranty terms" of Java generics: if a ClassCastException is raised, it will be associated with a cast in the source code, not an invisible cast inserted by the compiler.
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Difference between signed / unsigned char [duplicate]
So I know that the difference between a signed int and unsigned int is that a bit is used to signify if the number if positive or negative, but how does this apply to a char ? How can a character be positive or negative?
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How do I alter the position of a column in a PostgreSQL database table?
... SQL syntax.
One other idea occurs to me: you can define a VIEW that specifies the order of columns how you like it, without changing the physical position of the column in the base table.
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How to change the Push and Pop animations in a navigation based app
...t work, is explained in this post.
Just to repeat:
Surprisingly: with iOS, if you want the simplest, most common, everyday transitions (such as an ordinary slide), you do have to all the work of implementing a full custom transition.
Here's how to do it ...
1. You need a custom UIViewControllerAnima...
What does the restrict keyword mean in C++?
...A hint only, so may do nothing and still be conforming
A restrict-qualified pointer (or reference)...
! ...is basically a
promise to the compiler that for the
scope of the pointer, the target of the pointer will only
be accessed through that pointer (and pointers copied...
Joins are for lazy people?
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Joining in the app server can be more efficient if joining on the database causes severe redundancy in the result set sent over the network. Consider tables A and B, where each row in A is associated with 20 rows in B, B has only 100 rows, and we want to fetch the first 10...
How to get the client IP address in PHP [duplicate]
...e IP can be an internal IP from the LAN behind the proxy.
This means that if you are going to save the $_SERVER['HTTP_X_FORWARDED_FOR'], make sure you also save the $_SERVER['REMOTE_ADDR'] value. E.g. by saving both values in different fields in your database.
If you are going to save the IP to a ...