我的代码有效.复制约10个表后,我收到错误.Dynamic SQL generation for the DeleteCommand is not supported against a SelectCommand that does not return any key column information.
好的,我知道我需要生成一个主键.但为什么我可以复制10个左右的表,然后我得到错误.每行都必须返回主键吗?如果一行没有主键,我该如何生成一个?
这是我的代码:
using System; using System.Collections.Generic; using System.Data; using System.Data.OleDb; using System.IO; using System.Linq; using System.Text; namespace LCR_ShepherdStaffupdater_1._0 { public class DatabaseHandling { static DataTable datatableB = new DataTable(); static DataTable datatableA = new DataTable(); public static DataSet datasetA = new DataSet(); public static DataSet datasetB = new DataSet(); static OleDbDataAdapter adapterA = new OleDbDataAdapter(); static OleDbDataAdapter adapterB = new OleDbDataAdapter(); static string connectionstringA = "Provider=Microsoft.Jet.OLEDB.4.0;" + "Data Source=" + Settings.getfilelocationA(); static string connectionstringB = "Provider=Microsoft.Jet.OLEDB.4.0;" + "Data Source=" + Settings.getfilelocationB(); static OleDbConnection dataconnectionB = new OleDbConnection(connectionstringB); static OleDbConnection dataconnectionA = new OleDbConnection(connectionstringA); static DataTable tableListA; static DataTable tableListB; static public void addTableA(string table, bool addtoDataSet) { dataconnectionA.Open(); datatableA = new DataTable(table); try { OleDbCommand commandselectA = new OleDbCommand("SELECT * FROM [" + table + "]", dataconnectionA); adapterA.SelectCommand = commandselectA; adapterA.Fill(datatableA); } catch { Logging.updateLog("Error: Tried to get " + table + " from DataSetA. Table doesn't exist!", true, false, false); } if (addtoDataSet == true) { datasetA.Tables.Add(datatableA); Logging.updateLog("Added DataTableA: " + datatableA.TableName.ToString() + " Successfully!", false, false, false); } dataconnectionA.Close(); } static public void addTableB(string table, bool addtoDataSet) { dataconnectionB.Open(); datatableB = new DataTable(table); try { OleDbCommand commandselectB = new OleDbCommand("SELECT * FROM [" + table + "]", dataconnectionB); adapterB.SelectCommand = commandselectB; adapterB.Fill(datatableB); } catch { Logging.updateLog("Error: Tried to get " + table + " from DataSetB. Table doesn't exist!", true, false, false); } if (addtoDataSet == true) { datasetB.Tables.Add(datatableB); Logging.updateLog("Added DataTableB: " + datatableB.TableName.ToString() + " Successfully!", false, false, false); } dataconnectionB.Close(); } static public string[] getTablesA(string connectionString) { dataconnectionA.Open(); tableListA = dataconnectionA.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, new Object[] { null, null, null, "TABLE" }); string[] stringTableListA = new string[tableListA.Rows.Count]; for (int i = 0; i < tableListA.Rows.Count; i++) { stringTableListA[i] = tableListA.Rows[i].ItemArray[2].ToString(); } dataconnectionA.Close(); return stringTableListA; } static public string[] getTablesB(string connectionString) { dataconnectionB.Open(); tableListB = dataconnectionB.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, new Object[] { null, null, null, "TABLE" }); string[] stringTableListB = new string[tableListB.Rows.Count]; for (int i = 0; i < tableListB.Rows.Count; i++) { stringTableListB[i] = tableListB.Rows[i].ItemArray[2].ToString(); } dataconnectionB.Close(); return stringTableListB; } static public void createDataSet() { string[] tempA = getTablesA(connectionstringA); string[] tempB = getTablesB(connectionstringB); int percentage = 0; int maximum = (tempA.Length + tempB.Length); Logging.updateNotice("Loading Tables..."); Logging.updateLog("Started Loading File A", false, false, true); for (int i = 0; i < tempA.Length ; i++) { if (!datasetA.Tables.Contains(tempA[i])) { addTableA(tempA[i], true); percentage++; Logging.loadStatus(percentage, maximum); } else { datasetA.Tables.Remove(tempA[i]); addTableA(tempA[i], true); percentage++; Logging.loadStatus(percentage, maximum); } } Logging.updateLog("Finished loading File A", false, false, true); Logging.updateLog("Started loading File B", false, false, true); for (int i = 0; i < tempB.Length ; i++) { if (!datasetB.Tables.Contains(tempB[i])) { addTableB(tempB[i], true); percentage++; Logging.loadStatus(percentage, maximum); } else { datasetB.Tables.Remove(tempB[i]); addTableB(tempB[i], true); percentage++; Logging.loadStatus(percentage, maximum); } } Logging.updateLog("Finished loading File B", false, false, true); Logging.updateLog("Both files loaded into memory successfully", false, true, false); } static public DataTable getDataTableA() { datatableA = datasetA.Tables[Settings.textA]; return datatableA; } static public DataTable getDataTableB() { datatableB = datasetB.Tables[Settings.textB]; return datatableB; } static public DataSet getDataSetA() { return datasetA; } static public DataSet getDataSetB() { return datasetB; } static public void InitiateCopyProcessA() { DataSet tablesA; tablesA = DatabaseHandling.getDataSetA(); int percentage = 0; int maximum = (tablesA.Tables.Count); foreach (DataTable table in tablesA.Tables) { Logging.loadStatus(percentage, maximum); OverwriteTable(table, table.TableName); Logging.updateLog("Copied " + table.TableName + " successfully.", false, true, false); percentage++; } } static void OverwriteTable(DataTable sourceTable, string tableName) { using (var destConn = new OleDbConnection(connectionstringA)) using (var destCmd = new OleDbCommand(tableName, destConn) { CommandType = CommandType.TableDirect }) using (var destDA = new OleDbDataAdapter(destCmd)) { // Since we're using a single table, we can have the CommandBuilder // generate the appropriate INSERT and DELETE SQL statements using (var destCmdB = new OleDbCommandBuilder(destDA)) { destCmdB.QuotePrefix = "["; // quote reserved column names destCmdB.QuoteSuffix = "]"; destDA.DeleteCommand = destCmdB.GetDeleteCommand(); destDA.InsertCommand = destCmdB.GetInsertCommand(); // Get rows from destination, and delete them var destTable = new DataTable(); destDA.Fill(destTable); foreach (DataRow dr in destTable.Rows) { dr.Delete(); } destDA.Update(destTable); // Set rows from source as Added, so the DataAdapter will insert them foreach (DataRow dr in sourceTable.Rows) { dr.SetAdded(); } destDA.Update(sourceTable); } } } } }
Google对此并不是很有帮助.请提供编码示例.