Question

I will explain firstly what I do, then I will specify where is the problem.

My application gets an XML file from an authenticated user through (file uploader), then I map (I mean migrate) the data stored in the XML file to its equivalent one in my database.
I get the data from the XML file through LINQ.

• My first question

  Each element in
  the XML file has an equivalent entity
  in my database. What is the best and
  more performant way to insert
  more than one record in a
  specific table and guarantee that if
  there is something wrong in the data, rollback the whole operation?
  Is there some example of how to do
  this? Do you have any suggestions concerning
  validating the XML data?

• My second question:

  In the first question, I talk about the
  the (INSERT) operation. If the
  user changes some data in the XML
  file then I want to update my
  database with the new data. How should I
  do this? Should I compare each
  record, or try to insert and, if that fails,
  then update this record?

Answer 1

each element in the XML file has an
equivalent entity in my database. What
is the best and more performance way
to insert more than one record in a
specific table .and guarantee if there
is some thing wrong in the data ,
rollback the whole operation .please
if there is some sample to do this.and
any suggestions concerning validating
the XML data.

The simple answer here is: use a transaction. The point of transactions is to provide you with a mechanism whereby you can execute multiple commands, then either commit them as a single unit of work or roll them back completely so that the database is left in a state as if your operations had never taken place.

in the first one i talk about the the
(INSERT) operation, if the user change
some data in the XML file then i wanna
to update my database with the new
data.how to o this .should i compare
each record . or try to insert if fail
then update this record?.

The try-error-different retry pattern is not a desirable one if it can be easily avoided. Your SQL should either use a statement that is designed to conditionally insert or update depending on existing data (such as the SQL Server MERGE command; I don’t have Informix experience so I can’t speak to what it supports or if MERGE is ANSI SQL), or you should do this conditional logic yourself within the SQL.