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Correct way to use StringBuilder in SQL
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The aim of using StringBuilder, i.e reducing memory. Is it achieved?
No, not at all. That code is not using StringBuilder correctly. (I think you've misquoted it, though; surely there aren't quotes around id2 and table?)
Note that the aim ...
Why is it slower to iterate over a small string than a small list?
...ith timeit and noticed that doing a simple list comprehension over a small string took longer than doing the same operation on a list of small single character strings. Any explanation? It's almost 1.35 times as much time.
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How to extract year and month from date in PostgreSQL without using to_char() function?
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what are you trying to do? Just get a string? Then use to_char function with a date format you need postgresql.org/docs/8.2/static/functions-formatting.html
– MK.
Apr 24 '17 at 17:22
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What differences, if any, between C++03 and C++11 can be detected at run-time?
...isCpp0x() {
return (sizeof c::a()) == sizeof(b);
}
Also, the fact that string literals do not anymore convert to char*
bool isCpp0xImpl(...) { return true; }
bool isCpp0xImpl(char*) { return false; }
bool isCpp0x() { return isCpp0xImpl(""); }
I don't know how likely you are to have this work...
Is a colon `:` safe for friendly-URL use?
...ndards are conflicting. For example HTTP/1.1 RFC 2616 does not allow query string in the request URL, while HTML constructs one when submitting a form with GET method. Whichever implemented in the real world wins at the end of the day.
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How can I reliably determine the type of a variable that is declared using var at design time?
...ainst just that statement. For example, suppose you have the method body:
String x = "hello";
var y = x.ToCharArray();
var z = from foo in y where foo.
and now we need to work out that foo is of type char. We build a database that has all the metadata, extension methods, source code types, and so...
PHP - iterate on string characters
Is there a nice way to iterate on the characters of a string? I'd like to be able to do foreach , array_map , array_walk , array_filter etc. on the characters of a string.
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Find a string by searching all tables in SQL Server Management Studio 2008
Is there any way to search for a string in all tables of a database in SQL Server Management Studio 2008?
8 Answers
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What are copy elision and return value optimization?
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Copy elision is an optimization implemented by most compilers to prevent extra (potentially expensive) copies in certain situations. It makes returning by value or pass-by-value feasible in practice (restrictions apply).
It's the only form of optimization that elides (ha!) the as-if rule - copy el...
How to convert an enum type variable to a string?
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There really is no beautiful way of doing this. Just set up an array of strings indexed by the enum.
If you do a lot of output, you can define an operator<< that takes an enum parameter and does the lookup for you.
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