使用insert命令通过ado.net C＃访问数据库时出现“连接错误”

Question

I write code to insert some values to access database with C#/ado.net but there is an error appear called "error in connection" although i use select command to retrieve some valuesin the same program and works successfully

OleDbConnection conn = new OleDbConnection(@"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:\Users\Mohamed\documents\visual studio 2012\Projects\Library Store\Library Store\Book.accdb");

conn.Open();
OleDbCommand cmd = new OleDbCommand("INSERT INTO Store VALUES (@val1,@val2,@val3,@val4,@val5,@val6)", conn);
cmd.Parameters.AddWithValue("@val1", ISBNTB.Text.Trim());
cmd.Parameters.AddWithValue("@val2", NameTB.Text.Trim());
cmd.Parameters.AddWithValue("@val3", GategoryTB.Text.Trim());
cmd.Parameters.AddWithValue("@val4", AuthorTB.Text.Trim());
cmd.Parameters.AddWithValue("@val5", int.Parse(CostTB.Text.Trim()));
cmd.Parameters.AddWithValue("@val6", dateTimePicker1.Text);
cmd.ExecuteNonQuery();
MessageBox.Show(" Done :)");
conn.Close();

thanks;

Answer 1

Give this a shot, you didn't specify what error it was but this should help you out if anythign figure out if you really have all columns your trying to insert to

Try writing you sql statement like so

INSERT INTO Table ( Column1, Column2 ) VALUES ( Value1, Value2 ), ( Value1, Value2 )

---

OleDbConnection conn = new OleDbConnection(@"Provider=Microsoft.ACE.OLEDB.12.0;Data     Source=C:\Users\Mohamed\documents\visual studio 2012\Projects\Library Store\Library     Store\Book.accdb");

conn.Open();
OleDbCommand cmd = new OleDbCommand("INSERT INTO Store **( Column1, Column2 )** VALUES(@val1,@val2,@val3,@val4,@val5,@val6)", conn);
cmd.Parameters.AddWithValue("@val1", ISBNTB.Text.Trim());
cmd.Parameters.AddWithValue("@val2", NameTB.Text.Trim());
cmd.Parameters.AddWithValue("@val3", GategoryTB.Text.Trim());
cmd.Parameters.AddWithValue("@val4", AuthorTB.Text.Trim());
cmd.Parameters.AddWithValue("@val5", int.Parse(CostTB.Text.Trim()));
cmd.Parameters.AddWithValue("@val6", dateTimePicker1.Text);
cmd.ExecuteNonQuery();
MessageBox.Show(" Done :)");
conn.Close();

Answer 2

您需要在insert语句中指定列名，以便DB知道数据的去向。

"INSERT INTO Store (Column1, Column2) VALUES (@val1, @val2)"

Answer 3

If you insert value to database with all column you can use this query

INSERT INTO Store  VALUES(@val1,@val2,@val3,@val4,@val5,@val6)

If you insert value to database with few column you will get this error, and you must write it as

INSERT INTO Store **( Column1, Column2 )** VALUES(@val1,@val2,@val3,@val4,@val5,@val6)