使用SqlDataAdapter更新SQL Server数据库

Question

I have a DataTable with new entries, and I want to add these to an existing database.

So I create a SqlDataAdapter and fill a second table with it, then I merge the two tables, and update the database, but nothing happens, the return value is 0, the database stays the same.

Here's my code:

DBManager.DBDestinationConnect(textBox10.Text, textBox9.Text, textBox8.Text, textBox7.Text, ref destinationConnection);
//DBManager is a Class, to connect with the database
CategoryAdapterBackup = new SqlDataAdapter("SELECT*FROM " + tablename, destinationConnection);

CategoryTableBackup = new DataTable();
CategoryAdapterBackup.Fill(CategoryTableBackup);
CategoryTableBackup.Merge(SubTable);

//SubTable is the DataTable with the new entries
CategoryAdapterBackup.Update(CategoryTableBackup);

Answer 1

也可以尝试使用CategoryAdapterBackup.Flush()或DBManager.Flush() ，将SELECT*FROM替换为SELECT * FROM （带空格）

Answer 2

I'm having a problem discerning your intentions with this code. Why not simply use sqlbulkcopy on SubTable? That would append the contents of SubTable to the destination SQL table. If you are afraid of duplicates, then insert the contents of SubTable Table to a Temp in the DB and maybe use a Join to insert rows into the destination table where not exists row in destination table.