An example of a cursor you can find in this post http://www.sqlservercentral.com/articles/cursors/65136/, but don't forget to read the discution for there is some discution possible wether it is a good thing to use cursor.

For the error-handling

-- Error-declarations --

DECLARE@MyErrNumber int,

@MyErrSeverity int,

@MyErrState int,

@MyErrLine int,

@MyErrProcedure nvarchar(128),

@MyErrMessage nvarchar(4000);

SET @MyErrNumber = 0

--

BEGIN TRY

-- execution (begin)

-- execution (end)

END TRY

BEGIN CATCH

SELECT @MyErrNumber = ERROR_NUMBER(),

@MyErrSeverity = ERROR_SEVERITY(),

@MyErrState = ERROR_STATE(),

@MyErrLine = ERROR_LINE (),

@MyErrProcedure = ERROR_PROCEDURE(),

@MyErrMessage = ERROR_MESSAGE()

select @MyErrNumber As ErrNumber

,@MyErrSeverity As ErrSeverity

,@MyErrState As ErrState

,@MyErrLine As ErrLine

,@MyErrProcedure As ErrProcedure

,@MyErrMessage As ErrMessage ;

-- close open transactions (only valid for transactions in try-block)

IF @@TRANCOUNT > 1

BEGIN

ROLLBACK TRAN

END

-- DO something with error-values here

END CATCH;