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How many database indexes is too many?
...nds on the operations that occur on the table.
If there's lots of SELECTs and very few changes, index all you like.... these will (potentially) speed the SELECT statements up.
If the table is heavily hit by UPDATEs, INSERTs + DELETEs ... these will be very slow with lots of indexes since they all ...
Why doesn't delete set the pointer to NULL?
...tomatic setting of the pointer to NULL after delete is not part of the standard. If this gets taken care of then many of the crashes due to an invalid pointer would not occur. But having said that I can think of couple of reasons why the standard would have restricted this:
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Disable JavaScript error in WebBrowser control
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This disables the script errors and also disables other windows.. such as the NTLM login window or the client certificate accept window. The below will suppress only javascript errors.
// Hides script errors without hiding other dialog boxes.
private voi...
C++ Double Address Operator? (&&)
I'm reading STL source code and I have no idea what && address operator is supposed to do. Here is a code example from stl_vector.h :
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Postgresql SELECT if string contains
...concatenated, no chance for SQL injection.
– Erwin Brandstetter
Apr 27 '14 at 10:48
1
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Insert a string at a specific index
...d changes the content of a string by removing a range of
* characters and/or adding new characters.
*
* @this {String}
* @param {number} start Index at which to start changing the string.
* @param {number} delCount An integer indicating the number of old chars to remove.
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Can I use a hash sign (#) for commenting in PHP?
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The answer to the question Is there any difference between using "#" and "//" for single-line comments in PHP? is no.
There is no difference. By looking at the parsing part of PHP source code, both "#" and "//" are handled by the same code and therefore have the exact same behavior.
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JavaScript closures vs. anonymous functions
A friend of mine and I are currently discussing what is a closure in JS and what isn't. We just want to make sure we really understand it correctly.
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What is the maximum possible length of a .NET string?
...owhere near that. Since no single object in a .NET program may be over 2GB and the string type uses UTF-16 (2 bytes for each character), the best you could do is 1,073,741,823, but you're not likely to ever be able to allocate that on a 32-bit machine.
This is one of those situations where "If you ...
change type of input field with jQuery
...with id="password" ) that is of type password to a normal text field, and then fill in the text “Password”.
29 Ans...