SQL内部连接和普通选择

Question

how can i normally select table/column in inner join query?

look at this code SQL CODE HERE

this is how i populate my dgv

SqlConnection con = new SqlConnection("Data Source=DESKTOP-5V9PS33\\SQLEXPRESS;Initial Catalog=Farmacia;Integrated Security=True");
            con.Open();
            SqlCommand sc = new SqlCommand("SELECT Category,Subcategory,Product,Supplier FROM Inventory Inner Join Category ON Category.ID = Inventory.CategoryID Inner Join Subcategory ON Subcategory.ID = Inventory.SubcategoryID Inner Join Product ON Product.ID = Inventory.ProductID Inner Join Supplier ON Supplier.ID = Inventory.SupplierID", con);
            SqlDataReader reader;
            reader = sc.ExecuteReader();
            DataTable dt = new DataTable();
            dt.Columns.Add("ID", typeof(int));
            dt.Columns.Add("Product", typeof(string));
            dt.Columns.Add("Category", typeof(string));
            dt.Columns.Add("Subcategory", typeof(string));
            dt.Columns.Add("Supplier", typeof(string));
            dt.Load(reader);

            for (int x = 0; x < dt.Rows.Count; x++)
            {
                string ID = dt.Rows[x].ItemArray[0].ToString();
                string Product = dt.Rows[x].ItemArray[1].ToString();
                string Category = dt.Rows[x].ItemArray[2].ToString();
                string Subcategory = dt.Rows[x].ItemArray[3].ToString();
                string Supplier = dt.Rows[x].ItemArray[4].ToString();
                string[] row = { ID,Product, Category, Subcategory, Supplier };
                dgvInventory.Rows.Add(row);

            }

i need to output the ID together with the other information in one query so i can put them into one datatable then populate the DGV with it

Answer 1

将Inventory.Id添加到您select查询中。

SELECT Inventory.Id, Category,Subcategory,Product,Supplier FROM Inventory ...