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What is the difference between 127.0.0.1 and localhost
...hen (intelligent) software will just turn that directly into an IP address and use it. Some implementations of gethostbyname will detect the dotted format (and presumably the equivalent IPv6 format) and not do a lookup at all.
Otherwise, the name has to be resolved. And there's no guarantee that yo...
How to declare a variable in MySQL?
... refer to a variable that has not been
initialized, it has a value of NULL and a type of string.
SELECT @var_any_var_name
You can initialize a variable using SET or SELECT statement:
SET @start = 1, @finish = 10;
or
SELECT @start := 1, @finish := 10;
SELECT * FROM places WHERE place BET...
MySQL connection not working: 2002 No such file or directory
I'm trying to set up WordPress. I have Apache and MySQL running, and the accounts and database are all set up. I tried to make a simple connection:
...
How can I know which parts in the code are never used?
..., it's much more difficult. Statically it requires whole program analysis, and even though link time optimization may actually remove dead code, in practice the program has been so much transformed at the time it is performed that it is near impossible to convey meaningful information to the user.
...
Which “href” value should I use for JavaScript links, “#” or “javascript:void(0)”?
...false;
}
But then they forget to use return doSomething() in the onclick and just use doSomething().
A second reason for avoiding # is that the final return false; will not execute if the called function throws an error. Hence the developers have to also remember to handle any error appropriately...
Which is better option to use for dividing an integer number by 2?
...f the following techniques is the best option for dividing an integer by 2 and why?
23 Answers
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Using arrays or std::vectors in C++, what's the performance gap?
...hould be avoided. There is the problem you have to keep track of the size, and you need to delete them manually and do all sort of housekeeping.
Using arrays on the stack is also discouraged because you don't have range checking, and passing the array around will lose any information about its siz...
Better way to check if a Path is a File or a Directory?
I am processing a TreeView of directories and files. A user can select either a file or a directory and then do something with it. This requires me to have a method which performs different actions based on the user's selection.
...
git diff file against its last change
...ble to get git to produce a diff between a specific file as it exists now, and as it existed before the last commit that changed it?
...
Base64 length calculation?
... * 6 = 24 bits = 3 bytes.
So you need 4*(n/3) chars to represent n bytes, and this needs to be rounded up to a multiple of 4.
The number of unused padding chars resulting from the rounding up to a multiple of 4 will obviously be 0, 1, 2 or 3.
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