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IN vs OR in the SQL WHERE Clause
...rding to the manual for MySQL if the values are constant IN sorts the list and then uses a binary search. I would imagine that OR evaluates them one by one in no particular order. So IN is faster in some circumstances.
The best way to know is to profile both on your database with your specific dat...
What are carriage return, linefeed, and form feed?
...when the name was coined. This is commonly escaped as \r, abbreviated CR, and has ASCII value 13 or 0x0D.
Linefeed means to advance downward to the next line; however, it has been repurposed and renamed. Used as "newline", it terminates lines (commonly confused with separating lines). This is co...
Is either GET or POST more secure than the other?
...nformation as a GET in the actual network communication between the client and server. If you need to pass information that is sensitive, your first line of defense would be to pass it using Secure HTTP.
GET or query string posts are really good for information required for either bookmarking a p...
What does CultureInfo.InvariantCulture mean?
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Not all cultures use the same format for dates and decimal / currency values.
This will matter for you when you are converting input values (read) that are stored as strings to DateTime, float, double or decimal. It will also matter if you try to format the aforementio...
Find duplicate lines in a file and count how many time each line was duplicated?
...at should do the trick in O(n) * avg_line_len. Does anyone know such a commandline tool?
– Droggl
Nov 20 '13 at 17:27
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What are POD types in C++?
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POD stands for Plain Old Data - that is, a class (whether defined with the keyword struct or the keyword class) without constructors, destructors and virtual members functions. Wikipedia's article on POD goes into a bit more detail...
What is the difference between server side cookie and client side cookie?
What is the difference between creating cookies on the server and on the client? Are these called server side cookies and client side cookies? Is there a way to create cookies that can only be read on the server or on the client?
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Which characters need to be escaped in HTML?
...d in XML. Inside of an element, this just includes the entity escape ampersand & and the element delimiter less-than and greater-than signs < >:
& becomes &amp;
< becomes &lt;
> becomes &gt;
Inside of attribute values you must also escape the quote character you're ...
How to extract a floating number from a string [duplicate]
I have a number of strings similar to Current Level: 13.4 db. and I would like to extract just the floating point number. I say floating and not decimal as it's sometimes whole. Can RegEx do this or is there a better way?
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Determine Whether Two Date Ranges Overlap
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(StartA <= EndB) and (EndA >= StartB)
Proof:
Let ConditionA Mean that DateRange A Completely After DateRange B
_ |---- DateRange A ------|
|---Date Range B -----| _
(True if StartA >...