Question

I have a small console application written on C# .NET 2.0.
The application queries a database and takes a certain amount of id numbers, by which it then addresses a web service and get some “statuses” according to the id numbers.
Then the statuses are written back to the database.
Trough out the whole process I keep an open connection to the database, which I’m not sure to be the best way for batch processing as long as the application blocks the database engine and other clients are unable to work properly.
Opening and closing a connection for each operation does not seem wise as well.

What would be considered as the best way to handle those batch processes?

Answer 1

If you have loads of ids and want to update them all in a one go (a batch), you can form two CSV strings and pass them as parameters to a stored procedure(sp).

Also you need a function to split (Here are a few) those CSVs inside the sp and then update your table.

Ex;

//Make sure you have a relation between id and statusid here. i.e. same index
string csvIds = "101,2234,349,..."; //CSV for ids
string csvStatusIds = ="1,2,3,..."; //CSV for statusIds

//Pass above csv lists to the following stored procedure...

//Create a stored procedure to pass above ids.    
CREATE PROCEDURE [dbo].[updateStatuses] 

    @Ids VARCHAR(Max),
    @StatusIds VARCHAR(Max)

AS
BEGIN
     DECLARE @tblIds TABLE (key1 INT IDENTITY(1,1), myId INT)
     DECLARE @tblStatusIds TABLE (key2 INT IDENTITY(1,1), myStatusId INT)

     INSERT INTO @tblIds
        SELECT ITEMS FROM dbo.Split(@Ids,',')
     INSERT INTO @tblStatusIds
        SELECT ITEMS FROM dbo.Split(@StatusIds,',')

     --//Do your status update here
     UPDATE yt.statusId = s.myStatusId
     FROM [YourTable] yt JOIN @tblIds i 
                ON yt.id = i.myId JOIN @tblStatusIds s
                ON i.key1 = s.key2

END