将 CSV 加载到 MySQL 这是一个错误吗？ - 找不到文件异常

Question

我正在尝试将 CSV 文件加载到 C# 中的 MySQL 数据库中，但我不断收到无法从结果集中读取的异常。我在 MySQL 工作台中清理了语法，以至于我可以将 CSV 文件加载到 MySQL 工作台的数据库中而没有错误。在我的程序中尝试它，我仍然得到异常。我正在使用的文件具有以下路径和文件名：

D:\SANCentral\Customer Files\ibm\70738\0918\switch port.csv

我得到的异常是“无法从结果集中读取”。查看内部异常，我得到文件未找到。我不知道那是从哪里来的。 D:\Projects\CSVParser 是我的项目的位置。我假设 MySQL.Data.Client 类正在使用我给它的位置来打开文件。这显然是 SQL 命令试图从中加载文件的路径：

 {"Could not find file  'D:\\Projects\\CSVParser\\CSVParser\\bin\\Debug\\SANCentralCustomer Filesibm70738'
.":"D:\\Projects\\CSVParser\\CSVParser\\bin\\Debug\\SANCentralCustomer Filesibm70738"}

我该如何解决这个问题？我在调试器中检查了要解析的文件的路径，它是正确的。我尝试将 .CSV 文件移动到从中运行项目的项目目录中，但仍然出现异常，但它是路径中的非法字符，而不是找不到文件。

这是执行加载的 C# 代码和 MySQL 语句：

string ConnectionString =  String.Format(@"server=localhost;userid={0};
        password={1};database=PerformanceMonitors;
Allow User Variables=True", user,password);
        MySqlConnection sqlconnect = new MySqlConnection(ConnectionString);
        sqlconnect.Open();

这是 MySQL 语句并执行查询。抱歉，字符串有点长：

string working = String.Format(@"LOAD DATA LOCAL INFILE '{0}' IGNORE
INTO TABLE {1} COLUMNS TERMINATED BY ',' LINES TERMINATED BY '\n'
  IGNORE 1 LINES (`Switch`,`Port`,`WWPN`,@the_slot,`Port Index`,@the_time,
`Interval`,`Port Send Packet Rate`,  
`Port Receive Packet Rate`,`Total Port Packet Rate`,`Port Send Data Rate`, 
`Port Receive Data Rate`,`Total Port Data Rate`, 
Peak Send Data Rate`,`Port Peak Receive Data Rate`,

Port Send Packet Size,Port Receive Packet Size,Overall Port Packet Size,
Error Frame Rate,Dumped Frame Rate,
Link Failure Rate,Loss of Sync Rate,Loss of Signal Rate,CRC Error Rate344@98764 @,Long Frame Rate,Encoding Disparity Error Rate,
Discarded Class3 Frame Rate,F-BSY Frame Rate,F-RJT Frame Rate,
Port Send Bandwidth Percentage,Port Receive Bandwidth Percentage, Overall Port Bandwidth Percentage,Primitive Sequence Protocol Error Rate,
Invalid Transmission Word Rate,Link Reset Transmitted Rate,Link Reset Received Rate)

    SET Slot = nullif(@the_slot,''), Time= str_to_date(@the_time,'%m/%d/%y %h:%i %p')", files.FirstOrDefault().ToString(), "by_switch");


       string commandreplaced= working.Replace("\n", "");

        MySqlCommand cmd = new MySqlCommand(commandreplaced,sqlconnect);
        cmd.ExecuteNonQuery();

Answer 1

好吧，我终于找到了答案。 LOAD DATA FILE 语句要求文件名是字符串值，它不能被参数化。不幸的是，MySQLCommand 类不喜欢 C# 字符串对象的文件路径中的转义 \，因此它无法找到该文件。我通过逃避逃逸来让它工作：

//build the LOAD DATA File command
string working = String.Format("LOAD DATA LOCAL INFILE '{0}' IGNORE ", files.FirstOrDefault().ToString()) +
                         String.Format("INTO TABLE {0} COLUMNS TERMINATED BY ',' LINES TERMINATED BY '\n'", "by_switch")+
                         String.Format(" IGNORE 1 LINES (`Switch`,`Port`,`WWPN`,@the_slot,`Port Index`,@the_time,`Interval`,`Port Send Packet Rate`,")+
                         String.Format("`Port Receive Packet Rate`,`Total Port Packet Rate`,`Port Send Data Rate`,")+        
                         String.Format("`Port Receive Data Rate`,`Total Port Data Rate`,`Port Peak Send Data Rate`,`Port Peak Receive Data Rate`,")+ 
                         String.Format("`Port Send Packet Size`,`Port Receive Packet Size`,`Overall Port Packet Size`,`Error Frame Rate`,")+
                         String.Format("`Dumped Frame Rate`,`Link Failure Rate`,`Loss of Sync Rate`,`Loss of Signal Rate`,`CRC Error Rate`,")+
                         String.Format(" `Short Frame Rate`,`Long Frame Rate`,`Encoding Disparity Error Rate`,")+         
                         String.Format("`Discarded Class3 Frame Rate`,`F-BSY Frame Rate`,`F-RJT Frame Rate`, `Port Send Bandwidth Percentage`,")+
                         String.Format("`Port Receive Bandwidth Percentage`, `Overall Port Bandwidth Percentage`,`Primitive Sequence Protocol Error Rate`,")+
                         String.Format("`Invalid Transmission Word Rate`,`Link Reset Transmitted Rate`,`Link Reset Received Rate`)")+ 
                          String.Format("SET Slot = nullif(@the_slot,''),")+ 
                          String.Format(@"Time= str_to_date(@the_time,'%m/%d/%y %h:%i %p')");


// now escape the escape character
       commandreplaced = commandreplaced.Replace(@"\", @"\\");

   // now execute the command
        MySqlCommand cmd = new MySqlCommand(commandreplaced,sqlconnect);