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Can (domain name) subdomains have an underscore “_” in it?
...ntax" in Section 3.5 of RFC 1034 as modified by RFC 1123. Briefly, it is a string consisting of ASCII letters, digits, and the hyphen with the further restriction that the hyphen cannot appear at the beginning or end of the string. Like all DNS labels, its total length must not exceed 63 octets.
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How do I check to see if a value is an integer in MySQL?
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I'll assume you want to check a string value. One nice way is the REGEXP operator, matching the string to a regular expression. Simply do
select field from table where field REGEXP '^-?[0-9]+$';
this is reasonably fast. If your field is numeric, just tes...
Just what is an IntPtr exactly?
...oints to.
In other words, an IntPtr is just like a void* -- but with the extra feature that it can (but shouldn't) be used for basic pointer arithmetic.
In order to dereference an IntPtr, you can either cast it to a true pointer (an operation which can only be performed in "unsafe" contexts) or y...
Getting Java version at runtime
... version naming convention.
Sun Technical Articles
J2SE SDK/JRE Version String Naming Convention
Version 1.5.0 or 5.0?
"J2SE also keeps the version number 1.5.0 (or 1.5) in some places that are visible only to developers, or where the version number is parsed by programs"
"java.version system...
Using Rails 3.1, where do you put your “page specific” JavaScript code?
...I really like this solution. The only problem I have with it is that those extra manifests are not compressed/uglified. They are properly compiled though. Is there a solution or am I missing something?
– clst
Dec 8 '11 at 16:31
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Are foreign keys really necessary in a database design?
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That's a horrible answer FKs genaerally can add extra overhead not improve performance.
– Agile Jedi
Feb 13 '15 at 18:42
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Truncating floats in Python
...xplanation
The core of the underlying method is to convert the value to a string at full precision and then just chop off everything beyond the desired number of characters. The latter step is easy; it can be done either with string manipulation
i, p, d = s.partition('.')
'.'.join([i, (d+'0'*n)[:n...
Equivalent to 'app.config' for a library (DLL)
...code won't work properly.
Now to read from this file have such function:
string GetAppSetting(Configuration config, string key)
{
KeyValueConfigurationElement element = config.AppSettings.Settings[key];
if (element != null)
{
string value = element.Value;
if (!string.Is...
Get user profile picture by Id
...=picture.type(large) this is useful when you have something like this, String url = "graph.facebook.com/me?fields=id,name,email,picture.type(large) as mentioned in other answers you can replace large with normal,small,square...
– yajnesh
Dec 16 '15 at 11:4...
What is the pythonic way to detect the last element in a 'for' loop?
...t depends on what you are trying to do. For example, if you are building a string from a list, it's naturally better to use str.join() than using a for loop “with special case”.
Using the same principle but more compact:
for i, line in enumerate(data_list):
if i > 0:
between_i...