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This Row already belongs to another table error when trying to add rows?
I have a DataTable which has some rows and I am using the select to filter the rows to get a collection of DataRows which I then loop through using foreach and add it to another DataTable, but it is giving me the error "This Row already belongs to another table". Here is the code:
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What does the @ symbol represent in objective-c?
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The @ character isn't used in C or C++ identifiers, so it's used to introduce Objective-C language keywords in a way that won't conflict with the other languages' keywords. This enables the "Objective" part of the language to free...
How to get the max of two values in MySQL?
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Use GREATEST()
E.g.:
SELECT GREATEST(2,1);
Note: Whenever if any single value contains null at that time this function always returns null (Thanks to user @sanghavi7)
s...
Is there an easy way to attach source in Eclipse?
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Go to Properties (for the Project) -> Java Build Path -> Libraries
Select the Library you want to attach source/javadoc for and then expand it, you'll see a list like so:
Source Attachment: (none)
Javadoc location: (none)
Native library location: (none)
Access rules: (No restrictions)
Sel...
LINQ To Entities does not recognize the method Last. Really?
...e fact that eventually it has to translate that query to SQL and SQL has a SELECT TOP (in T-SQL) but not a SELECT BOTTOM (no such thing).
There is an easy way around it though, just order descending and then do a First(), which is what you did.
EDIT:
Other providers will possibly have different im...
What is the difference between the template method and the strategy patterns?
...atum); }
}
In summary:
Template method pattern: compile-time algorithm selection by subclassing
Strategy pattern: run-time algorithm selection by containment
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How to change the Eclipse default workspace?
...down>Workspaces.
There you can set a flag to make Eclipse prompt you to select a workspace at startup by checking the "Prompt for workspace at startup" checkbox.
You can set the number of previous workspaces to remember also. Finally there is a list of recent workspaces. If you just remove all b...
Compare dates in MySQL
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You can try below query,
select * from players
where
us_reg_date between '2000-07-05'
and
DATE_ADD('2011-11-10',INTERVAL 1 DAY)
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“Insert if not exists” statement in SQLite
... and text you should be able to do like this:
INSERT INTO memos(id,text)
SELECT 5, 'text to insert'
WHERE NOT EXISTS(SELECT 1 FROM memos WHERE id = 5 AND text = 'text to insert');
If a record already contains a row where text is equal to 'text to insert' and id is equal to 5, then the insert op...
How can i query for null values in entity framework?
...try in table
where entry.something.Equals(value)
select entry;
Workaround for Linq-to-Entities (ouch!):
var result = from entry in table
where (value == null ? entry.something == null : entry.something == value)
select entry;
This is a nasty b...