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What is this operator in MySQL?
...a' <=> NULL)
Based on this, your particular query (fragment) can be converted to the more portable:
WHERE p.name IS NULL
Support
The SQL:2003 standard introduced a predicate for this, which works exactly like MySQL's <=> operator, in the following form:
IS [NOT] DISTINCT FROM
The fol...
When are C++ macros beneficial? [closed]
... FILE generates a string constant, which will be concatenated with the ":" into a single string by the pre-processor.
– Frank Szczerba
Mar 19 '09 at 23:59
12
...
Encoding URL query parameters in Java
...tricted to HTTP. Similarly, : is valid in a query string and should not be converted to %3B; a server can choose to interpret them differently.
– tc.
Mar 26 '13 at 18:38
1
...
Gitignore not working
...ce indicator at bottom right showing type of line endings. It was LF so I converted to CRLF as suggested but no dice.
Then I looked next to the line endings and noticed it was saved using UTF16. So I resaved using UTF8 encoding an voila, it worked. I didn't think the CRLF mattered so I changed i...
Hyphenated html attributes with asp.net mvc
...erscore in the data attribute name, and it'll magically handle it for you, converting it to a hyphen. It knows you want a hyphen rather than an underscore as underscores aren't valid in html attribute names.
<%= Html.TextBox("name", value, new { @data_foo = "bar"}) %>
...
Aborting a shell script if any command returns a non-zero value?
...r part of an && or || list.
See the bash(1) man page on the "set" internal command for more details.
I personally start almost all shell scripts with "set -e". It's really annoying to have a script stubbornly continue when something fails in the middle and breaks assumptions for the rest ...
How does RegexOptions.Compiled work?
...the regular expression engine to compile the regular expression expression into IL using lightweight code generation (LCG). This compilation happens during the construction of the object and heavily slows it down. In turn, matches using the regular expression are faster.
If you do not specify this ...
When do I use a dot, arrow, or double colon to refer to members of a class in C++?
...ect of a class that overloads operator-> (common such types are smart pointers and iterators), then the meaning is whatever the class designer implemented. To conclude: With a->b, if a is a pointer, b will be a member of the object the pointer a refers to. If, however, a is an object of a clas...
How can a Java variable be different from itself?
...Float.NaN:
float x = Float.NaN; // <--
if (x == x) {
System.out.println("Ok");
} else {
System.out.println("Not ok");
}
Not ok
You can do the same with Double.NaN.
From JLS §15.21.1. Numerical Equality Operators == and !=:
Floating-point equality testing is performed in accordance...
Is it better to use std::memcpy() or std::copy() in terms to performance?
... of its information. When you call std::copy, the function keeps the types intact. memcpy operates on void *, which discards almost all useful information. For instance, if I pass in an array of std::uint64_t, the compiler or library implementer may be able to take advantage of 64-bit alignment with...