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String is immutable. What exactly is the meaning? [duplicate]
...
A string is a char[] containing a series of UTF-16 code units, an int offset into that array, and an int length.
For example.
String s
It creates space for a string reference. Assigning copies references around but does not modify the...
Why use the SQL Server 2008 geography data type?
...tance < 500 * 1609.344
orderby distance
select f;
return q1.FirstOrDefault();
}
Then there is a very good reason to use Geography.
Explanation of spatial within Entity Framework.
Updated with Creating High Performance Spatial Databases
As I noted on Noe...
SQL how to make null values come last when sorting ascending
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select MyDate
from MyTable
order by case when MyDate is null then 1 else 0 end, MyDate
share
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improve this answer
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CSS Child vs Descendant selectors
I am a bit confused between these 2 selectors.
8 Answers
8
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How to fix .pch file missing on build?
...the bottom of the drop-down menu.
At the top left of the Properties Pages,
select All Configurations from the drop-down menu.
Open the C/C++ tree and select Precompiled Headers
Precompiled Header: Select Use (/Yu)
Fill in the Precompiled Header File field. Standard is stdafx.h
Click Okay
If you do n...
Using “like” wildcard in prepared statement
...place("[", "![");
PreparedStatement pstmt = con.prepareStatement(
"SELECT * FROM analysis WHERE notes LIKE ? ESCAPE '!'");
pstmt.setString(1, notes + "%");
or a suffix-match:
pstmt.setString(1, "%" + notes);
or a global match:
pstmt.setString(1, "%" + notes + "%");
...
Hidden Features of Xcode 4
... View > Utilities > Code Snippet Library. To add a new code snippet, select some text in the editor view and drag it into the snippet library. You can either drag a snippet out and drop it in your code to use it, or, much more conveniently, assign a completion shortcut to it.
When you type i...
Moving Files into a Real Folder in Xcode
... Xcode should now be red (that's OK!).
From the Identity and Type manager, select the Group in Xcode that you want to relocate, then click the folder icon from the info pane:
In the Finder selection dialog, locate the equivalent new folder you created for this group in step 2. All the files insid...
T-SQL stored procedure that accepts multiple Id values
...nguages only.
XML. Very good for inserting many rows; may be overkill for SELECTs.
Table of Numbers. Higher performance/complexity than simple iterative method.
Fixed-length Elements. Fixed length improves speed over the delimited string
Function of Numbers. Variations of Table of Numbers and fixed...
MySQL/SQL: Group by date only on a Datetime column
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Cast the datetime to a date, then GROUP BY using this syntax:
SELECT SUM(foo), DATE(mydate) FROM a_table GROUP BY DATE(a_table.mydate);
Or you can GROUP BY the alias as @orlandu63 suggested:
SELECT SUM(foo), DATE(mydate) DateOnly FROM a_table GROUP BY DateOnly;
Though I don't think...