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Why do I get “Procedure expects parameter '@statement' of type 'ntext/nchar/nvarchar'.” when I try t
...r because @SQL needs to be NVARCHAR
DECLARE @SQL VARCHAR(100)
SET @SQL = 'SELECT TOP 1 * FROM sys.tables'
EXECUTE sp_executesql @SQL
So:
DECLARE @SQL NVARCHAR(100)
SET @SQL = 'SELECT TOP 1 * FROM sys.tables'
EXECUTE sp_executesql @SQL
...
What is the difference between IQueryable and IEnumerable?
...es, meaning the custom query logic it receives, e.g., a predicate or value selector, is in the form of an expression tree instead of a delegate to a method.
IEnumerable<T> is great for working with sequences that are iterated in-memory, but
IQueryable<T> allows for out-of memory things ...
Get “Value” property in IGrouping
...
For any selected group,you could call
var selectedGroupValues=selectedGroup.SelectMany(x=>x);
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...
Adding Core Data to existing iPhone project
... files in the right pane (like in a Resources folder for safe keeping) and select to Add a New File, Click the Core Data tab when selecting your file type then Click 'Data Model', give it a name and click Next and Finish and it will add it to your project. When you click on this Model object you wil...
Convert columns to string in Pandas
...cated dtype.
object dtype breaks dtype-specific operations like DataFrame.select_dtypes(). There isn’t a clear way to select just text
while excluding non-text but still object-dtype columns.
When reading code, the contents of an object dtype array is less clear than 'string'.
See also the se...
Is there a way to get a collection of all the Models in your Rails app?
....
EDIT: Just for fun, I found a way to list all classes
Module.constants.select { |c| (eval c).is_a? Class }
EDIT: Finally succeeded in listing all models without looking at directories
Module.constants.select do |constant_name|
constant = eval constant_name
if not constant.nil? and constan...
Login failed for user 'DOMAIN\MACHINENAME$'
...curity >> Logins and right click on NT AUTHORITY\NETWORK SERVICE and select Properties
In newly opened screen of Login Properties, go to the “User Mapping” tab. Then, on the “User Mapping” tab, select the desired database – especially the database for which this error message is dis...
What do I have to do to get Core Data to automatically migrate models?
...oordinator: %@",error);
}
Then you need to do a little trick in xCode:
Select your xcdatamodel file
Select the Design Menu at the top - then Data Model - then choose Add Model Version
Your xcdatamodel file will then get moved into a new directory with the same name as your xcdatamodel file but w...
ASP.NET MVC Yes/No Radio Buttons with Strongly Bound Model MVC
...
The second parameter is selected, so use the ! to select the no value when the boolean is false.
<%= Html.RadioButton("blah", !Model.blah) %> Yes
<%= Html.RadioButton("blah", Model.blah) %> No
...
What should every developer know about databases? [closed]
...fluence that choice;
The concept of coverage (why you shouldn't just write SELECT *);
The difference between a clustered and non-clustered index;
Why more/bigger indexes are not necessarily better;
Why you should try to avoid wrapping filter columns in functions.
Designers should also be aware of ...