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Set value to NULL in MySQL
... can be inserted/updated without quotes:
INSERT INTO user (name, something_optional) VALUES ("Joe", NULL);
UPDATE user SET something_optional = NULL;
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C# code to validate email address
...e-mail addresses are more forgiving than you might first assume. These are all perfectly valid forms:
cog@wheel
"cogwheel the orange"@example.com
123@$.xyz
For most use cases, a false "invalid" is much worse for your users and future proofing than a false "valid". Here's an article that used to ...
Maximum number of records in a MySQL database table
... The poster is not asking about numeric or any other data types. . I really do not understand how this can be flagged as a correct answer. Though I must admit that the question is ambiguous we should distinguish between PK data type and maximum number of rows for a table.
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How to use java.net.URLConnection to fire and handle HTTP requests?
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First a disclaimer beforehand: the posted code snippets are all basic examples. You'll need to handle trivial IOExceptions and RuntimeExceptions like NullPointerException, ArrayIndexOutOfBoundsException and consorts yourself.
Preparing
We first need to know at least the URL and the c...
How to set top-left alignment for UILabel for iOS application?
...turn nil;
// set inital value via IVAR so the setter isn't called
_verticalAlignment = VerticalAlignmentTop;
return self;
}
-(VerticalAlignment) verticalAlignment
{
return _verticalAlignment;
}
-(void) setVerticalAlignment:(VerticalAlignment)value
{
_verticalAlignment = value...
How to change a table name using an SQL query?
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Use sp_rename:
EXEC sp_rename 'Stu_Table', 'Stu_Table_10'
You can find documentation on this procedure on MSDN.
If you need to include a schema name, this can only be included in the first parameter (that is, this cannot be use...
NPM cannot install dependencies - Attempt to unlock something which hasn't been locked
I've been trying to run an npm install on my package.json file, but I'm having a lot of trouble. It keeps saying "Error: Attempt to unlock XXX, which hasn't been locked" on all my dependences. Here's one of them:
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How can I configure the font size for the tree item in the package explorer in Eclipse?
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Does your Eclipse .ini file contain a reference to 'smallFonts?' On Mac you might see something like...
-Dorg.eclipse.swt.internal.carbon.smallFonts
If you remove this line, you'll see the font size in various views fatten up.
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How can I remove non-ASCII characters but leave periods and spaces using Python?
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You can filter all characters from the string that are not printable using string.printable, like this:
>>> s = "some\x00string. with\x15 funny characters"
>>> import string
>>> printable = set(string.printable)
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What is move semantics?
...regarding C++0x . Most of the new features made sense to me, and I am actually excited about C++0x now, with the exception of one. I still don't get move semantics ... What is it exactly?
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