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.NET unique object identifier
...he object. I don't know of any way of converting this into anything like a string etc. The value of the reference will change during compaction (as you've seen), but every previous value A will be changed to value B, so as far as safe code is concerned it's still a unique ID.
If the objects involve...
What's the difference between a catalog and a schema in a relational database?
...l point of view :
The catalog is the place where--among other things--all of the various schemas (external, conceptual, internal) and all of the corresponding mappings (external/conceptual, conceptual/internal) are kept.
In other words, the catalog contains detailed information (sometimes...
How to call any method asynchronously in c#
...to simplify the call without having to create delegates:
void Foo2(int x, string y)
{
return;
}
...
new Task(() => { Foo2(42, "life, the universe, and everything");}).Start();
I'm pretty sure (but admittedly not positive) that the C# 5 async/await syntax is just syntactic sugar around the ...
str.startswith with a list of strings to test for
...
str.startswith allows you to supply a tuple of strings to test for:
if link.lower().startswith(("js", "catalog", "script", "katalog")):
From the docs:
str.startswith(prefix[, start[, end]])
Return True if string starts with the prefix, otherwise return False. ...
MySQL SELECT WHERE datetime matches day (and not necessarily time)
... two DATE values, convert the DATE values to DATETIME values. If you use a string constant such as '2001-1-1' in a comparison to a DATE, cast the string to a DATE." So unless they are all the same type, it is best to explicitly cast them.
– techdude
Jun 24 '15...
Check that Field Exists with MongoDB
So I'm attempting to find all records who have a field set and isn't null.
4 Answers
4...
How to get the URL of the current page in C# [duplicate]
...
Try this :
string url = HttpContext.Current.Request.Url.AbsoluteUri;
// http://localhost:1302/TESTERS/Default6.aspx
string path = HttpContext.Current.Request.Url.AbsolutePath;
// /TESTERS/Default6.aspx
string host = HttpContext.Curren...
Python, add trailing slash to directory string, os independently
...ow can I add a trailing slash ( / for *nix, \ for win32) to a directory string, if the tailing slash is not already there? Thanks!
...
What do people find difficult about C pointers? [closed]
...duling, actual CPU operations, or assembly-level memory management isn't really required.
When I was teaching, I found the following holes in students' understanding to be the most common source of problems:
Heap vs Stack storage. It is simply stunning how many people do not understand this, even...
Getting HTTP code in PHP using curl
...
First make sure if the URL is actually valid (a string, not empty, good syntax), this is quick to check server side. For example, doing this first could save a lot of time:
if(!$url || !is_string($url) || ! preg_match('/^http(s)?:\/\/[a-z0-9-]+(.[a-z0-9-]+)*(:[0-9]+)?(\/....