I wonder if someone can help me translate a MySQL query to a (Db)LINQ statement.
I’ve made a test case for what I want to do, so data and structure are different than what I really want to do, but it’s just meant to get it working.
I开发者_如何学Pythonn a MySQL database I have this table:
CREATE TABLE `mytable1`
(
`id` int(11) NOT NULL AUTO_INCREMENT,
`number` int(11) NOT NULL,
`name` varchar(20) COLLATE latin1_general_ci NOT NULL,
PRIMARY KEY (`id`)
) ENGINE=MyISAM AUTO_INCREMENT=6 DEFAULT CHARSET=latin1 COLLATE=latin1_general_ci
This is the content
id number name
1 10 aaa
2 20 bbb
3 25 cccc
4 30 ddd
5 35 eee
I use DBLinq within C# to connect to this table. In the C# program, I also have a list like this:
List<myDataFields> myNewData = new List<myDataFields>();
With
public class myDataFields
{
public int number { get; set; }
public string name { get; set; }
}
Content of the list is:
number name
10 firstName
20 secondName
30 ThirdName
If the content of the list would be a table in mysql (table2), I could just update table1 with this query:
update mytable1,mytable2 set mytable1.name=mytable2.name where
mytable1.number=mytable2.number;
(in real life I actually have to match two columns to be a key)
The result will be
id number name
1 10 firstName
2 20 secondName
3 25 cccc
4 30 ThirdName
5 35 eee
But how can I update table1, using DBLinq and the List within c#?
Solved the problem like this:
List<myDataFields> myDFList = new List<myDataFields>();
myDFList.Add(new myDataFields { name= "name123", number= 20 });
myDFList.Add(new myDataFields { name = "name456", number = 35 });
int[] getNumbers = (from numbers in myDFList select numbers.number).ToArray();
var dataInDb = from x in _db.mytable1 where getNumbers.Contains(x.Number) select x;
foreach (var row in dataInDb)
{
row.Name = (from mdf in myDFList where mdf.number == row.Number select mdf.name).First();
}
_db.SubmitChanges();
If someone knows a better solutions, please let me know.
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