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Does using “new” on a struct allocate it on the heap or stack?
...tructor (e.g. new Guid()) or a parameterful constructor (e.g. new Guid(someString)). These generate significantly different IL. To understand why, you need to compare the C# and CLI specs: according to C#, all value types have a parameterless constructor. According to the CLI spec, no value types ha...
How is the AND/OR operator represented as in Regular Expressions?
..., "part2" (answer 2) or "part1, part2" (answer 3).
I now try to match the string given by the user with the following, automatically created, regex expression:
...
Assigning default value while creating migration file
...generator command either but was able to specify a default value for a new string column as follows by amending the generated migration file before applying "rake db:migrate":
class AddColumnToWidgets < ActiveRecord::Migration
def change
add_column :widgets, :colour, :string, default: 'red...
Using LIMIT within GROUP BY to get N results per group?
... on the rate column instead of the year column.
The maximum length of the string returned by GROUP_CONCAT is limited, so this works well if you need to select a few records for every group.
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Update Row if it Exists Else Insert Logic with Entity Framework
...pouse.
public class Person
{
public int Id { get; set; }
public string FirstName { get; set; }
public string LastName { get; set; }
public string MiddleName { get; set; }
public int Age { get; set; }
public int DocumentId {get; set;}
public virtual ICollection<...
How does one escape backslashes and forward slashes in VIM find/search?
For instance, if I wanted to a find and replace with strings containing backward or forward slashes, how would this be accomplished in vim? Thank you!
...
How to connect to SQL Server database from JavaScript in the browser?
...:
var connection = new ActiveXObject("ADODB.Connection") ;
var connectionstring="Data Source=<server>;Initial Catalog=<catalog>;User ID=<user>;Password=<password>;Provider=SQLOLEDB";
connection.Open(connectionstring);
var rs = new ActiveXObject("ADODB.Recordset");
rs.Open...
What does $1 [QSA,L] mean in my .htaccess file?
...ll be rewritten as index.php?url=olle).
QSA means that if there's a query string passed with the original URL, it will be appended to the rewrite (olle?p=1 will be rewritten as index.php?url=olle&p=1.
L means if the rule matches, don't process any more RewriteRules below this one.
For more co...
Get parts of a NSURL in objective-c
I have an NSString with the value of
2 Answers
2
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How do I set a column value to NULL in SQL Server Management Studio?
...value and clicking enter will not create a NULL value. If the column is a string datatype (varchar and the like), it will create an empty string. If the column is a numeric datatype (int and the like) it will pop up an Invalid Value error. And so on. NULL is the absence of a value, and is does no...