Question

我正在构建一个简单的销售点计划并处理“搜索发票”按钮，该按钮最多允许3个搜索条件（InvoiceID，ClientName和ClientID）。这些是名为“Invoicing”的表中3列的名称。

InvoiceID是Int32类型的关键列，ClientName类型为String，ClientID类型为Int32。 ClientName和ClientID搜索功能完善。

我的问题：如果我在select查询中包含InvoiceID，则会出现以下错误。我花了几天时间试图解决这个问题。

错误：Database Error: Datatype mismatch in criteria expression.

你有经验丰富的程序员可以帮助我吗？谢谢！

String connectionString = @"Provider=Microsoft.ACE.OLEDB.12.0;Data" + @" Source=TESTDB.accdb";
            String tableName = "Invoicing";
            String query = String.Format("select * from [{0}] where", tableName);
            //ADD IN SEARCH CRITERIA
            int filled = 0;
            if (invoiceBox.Text != "") { query += " InvoiceID='" + invoiceBox.Text+"'"; filled += 1; }
            /*if (DateCheckBox.Checked == true) 
            {
                if (filled>=1) { query += " and DateNTime='" + monthCalendar1.SelectionStart.ToString() + "'"; filled += 1; }
                else { query += " DateNTime='" + monthCalendar1.SelectionStart.ToString()+ "'"; filled += 1; }
            }
             * */
            if (ClientNameBox.Text != "") //Doesnot work
            {
                if (filled >= 1) { query += " and Client='" + ClientNameBox.Text + "'"; filled += 1; }
                else { query += " Client='" + ClientNameBox.Text + "'"; filled += 1; }
            }

            if (ClientIDBox.Text != "") //THIS search criteria works!!!!
            {
                if (filled >= 1) { query += " and ClientID='" + ClientIDBox.Text + "'"; filled += 1; }
                else { query += " ClientID='" + ClientIDBox.Text + "'"; filled += 1; }
            }
            //CHECK IF SEARCH CRITERIA ARE PRESENT
            if (filled < 1) { MessageBox.Show("At least One Search criteria above is required"); return; }

            DataSet dsInvoicing = new DataSet();
            OleDbConnection conn = new OleDbConnection(connectionString);
            try
            {
                //Open Database Connection
                conn.Open();
                OleDbDataAdapter daInvoicing = new OleDbDataAdapter(query, conn);
                //Fill the DataSet
                daInvoicing.Fill(dsInvoicing, tableName);
                //MessageBox.Show("dsInventory has "+dsInventory.Tables[0].Rows.Count+" search results");
                conn.Close();
               this.dataGridView1.DataSource = dsInvoicing.Tables[0];
            }
            catch (OleDbException exp){ MessageBox.Show("Database Error: " + exp.Message.ToString());}

需要更多信息？如果我提供的不够，我会发布更多。数据库信息或其他。

非常感谢所有程序员。

Answer 1

看起来数据库中InvoiceID的数据类型是某种数字类型。在查询中，您将其视为字符串。尽量不要将InvoiceID值包装在单引号中。

标准表达式中的数据类型不匹配。在选择查询c＃Access数据库中

1 个答案: