SQLITE3+ Catnap + MonoTouch alter table add column pb

I don't understand, here 开发者_运维百科is my problem :

   string sql="alter table mytable add CellarPosition integer; alter table mytable add Quantity integer;  alter table mytable add CreatingYear integer; alter table mytable add OptimalYear integer;";

                var command = new DbCommandSpec().SetCommandText(sql);

                unitofwork.Session.ExecuteNonQuery(command);

the only first alter table executes but the others does not . any suggestion?????

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It is possible that SQLite might not be able to chain several Alter table queries. I'd suggest doing them one at a time for simplicity.

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If it had been MySQL, you would do something like this: alter table mytable add CellarPosition integer ,add Quantity integer ,add CreatingYear integer ,add OptimalYear integer;