将值插入 mysql 数据库未按预期工作

Question

我尝试从 C# 中填充 mySQL/ MariaDB table。读取 table 并填充数据集有效。

table 结构及其键等已给出且无法更改：

CREATE TABLE `fhem`.`history` (TIMESTAMP TIMESTAMP, DEVICE varchar(32), TYPE varchar(32), EVENT varchar(512), READING varchar(32), VALUE varchar(32), UNIT varchar(32));
CREATE TABLE `fhem`.`current` (TIMESTAMP TIMESTAMP, DEVICE varchar(32), TYPE varchar(32), EVENT varchar(512), READING varchar(32), VALUE varchar(32), UNIT varchar(32));
CREATE INDEX Search_Idx ON `fhem`.`history` (DEVICE, READING, TIMESTAMP);

这是我连接到数据库的代码，创建 sql 命令和适配器，然后用数据库 table 中的数据填充数据集。然后我创建一个新的数据行，用值填充列并将其添加到数据集的数据表中。

    class Program
    {
        static void Main(string[] args)
        {
            MySqlConnectionStringBuilder connBuilder = new MySqlConnectionStringBuilder();

            connBuilder.Server = "ds2";
            connBuilder.Database = "fhem";
            connBuilder.UserID = "fhemdbuser";
            connBuilder.Port = 3307;
            connBuilder.Password = "!2345Abcde";
            //connBuilder.DefaultCommandTimeout = 120;
            //connBuilder.UseDefaultCommandTimeoutForEF = true;
            //connBuilder.AllowUserVariables = true;

            MySqlConnection conn = new MySqlConnection(connBuilder.ConnectionString);
            conn.Open();
            MySqlCommand selectCmdCurrent = new MySqlCommand("select `TIMESTAMP`, `DEVICE`, `TYPE`, `EVENT`, `READING`, `VALUE`, `UNIT` from current;", conn);
            MySqlCommand selectCmdCurrentTest = new MySqlCommand("select `TIMESTAMP`, `DEVICE`, `TYPE`, `EVENT`, `READING`, `VALUE`, `UNIT` from currentTest;", conn);
            MySqlCommand updateCmd = new MySqlCommand("update `currentTest` set `TIMESTAMP`=@p1,`DEVICE`=@p2,`TYPE`=@p3,`EVENT`=@p4,`READING`=@p5,`VALUE`=@p6,`UNIT`=@p7", conn);
            updateCmd.Parameters.Add("@p1", MySql.Data.MySqlClient.MySqlDbType.DateTime);
            updateCmd.Parameters.Add("@p2", MySql.Data.MySqlClient.MySqlDbType.VarString, 128);
            updateCmd.Parameters.Add("@p3", MySql.Data.MySqlClient.MySqlDbType.VarString, 128);
            updateCmd.Parameters.Add("@p4", MySql.Data.MySqlClient.MySqlDbType.VarString, 512);
            updateCmd.Parameters.Add("@p5", MySql.Data.MySqlClient.MySqlDbType.VarString, 128);
            updateCmd.Parameters.Add("@p6", MySql.Data.MySqlClient.MySqlDbType.VarString, 128);
            updateCmd.Parameters.Add("@p7", MySql.Data.MySqlClient.MySqlDbType.VarString, 128);

            MySqlCommand insertCmd = new MySqlCommand("insert into `currentTest` values(@p1, @p2, @p3, @p4, @p5, @p6, @p7)", conn);
            insertCmd.Parameters.Add("@p1", MySql.Data.MySqlClient.MySqlDbType.DateTime);
            insertCmd.Parameters.Add("@p2", MySql.Data.MySqlClient.MySqlDbType.VarString, 128);
            insertCmd.Parameters.Add("@p3", MySql.Data.MySqlClient.MySqlDbType.VarString, 128);
            insertCmd.Parameters.Add("@p4", MySql.Data.MySqlClient.MySqlDbType.VarString, 512);
            insertCmd.Parameters.Add("@p5", MySql.Data.MySqlClient.MySqlDbType.VarString, 128);
            insertCmd.Parameters.Add("@p6", MySql.Data.MySqlClient.MySqlDbType.VarString, 128);
            insertCmd.Parameters.Add("@p7", MySql.Data.MySqlClient.MySqlDbType.VarString, 128);
            MySqlDataAdapter dataAdapterCurrent = new MySqlDataAdapter(selectCmdCurrent);
            MySqlDataAdapter dataAdapterCurrentTest = new MySqlDataAdapter(selectCmdCurrentTest);
            // MySqlCommandBuilder builder = new MySqlCommandBuilder(dataAdapterCurrent);
            dataAdapterCurrentTest.InsertCommand = insertCmd;
            dataAdapterCurrentTest.UpdateCommand = updateCmd;
            DataSet ds = new DataSet();
            MySqlCommand prepareCmd = new MySqlCommand("truncate currentTest;", conn);
            prepareCmd.ExecuteNonQuery();
            //prepareCmd = new MySqlCommand("insert into currentTest select * from current;", conn);
            //prepareCmd.ExecuteNonQuery();
            prepareCmd = new MySqlCommand("INSERT INTO `currentTest` VALUES(\"2020-06-06 12:45:23\",\"DEVICE\", \"TYPE\", \"EVENT\", \"READING\", \"VALUE\", \"UNIT\")", conn);
            for (int i = 0; i < 10; i++)
                prepareCmd.ExecuteNonQuery();
            dataAdapterCurrentTest.Fill(ds, "currentTest");
            dataAdapterCurrent.Fill(ds, "current");
            int row = 0;

            Stopwatch sw = new Stopwatch();
            for (int i = 0; i < 10; i++)
            {

                DataRow newrow = ds.Tables["currentTest"].NewRow();
                newrow["Timestamp"] = DateTime.Now;
                newrow["Device"] = "Device";
                newrow["TYPE"] = "Type";
                newrow["EVENT"] = "Event";
                newrow["READING"] = "Reading";
                newrow["VALUE"] = "Value";
                newrow["UNIT"] = "Unit";
                ds.Tables["currentTest"].Rows.Add(newrow);
            }
            dataAdapterCurrentTest.Update(ds.Tables["currentTest"]);
            ds.Tables["currentTest"].AcceptChanges();
        }
    }

虽然手动插入命令将正确的值放入数据库，但通过

的编程方法

DataRow newrow = ds.Tables["currentTest"].NewRow();
ds.Tables["currentTest"].Rows.Add(newrow);
dataAdapterCurrentTest.Update(ds.Tables["currentTest"]);
ds.Tables["currentTest"].AcceptChanges();

仅添加具有有效日期的行，但其他列为 NULL。

[编辑#1]：我对我的代码做了一些更改，基本上我修改了第二个 for 循环以插入新数据，就像我在第一个循环中所做的那样。然后数据被正确写入数据库。但我怀疑，调用 .ExecuteNonQuery() 数千次以将我的日志文件放入数据库是否是一种高效的方法...

[编辑#2]： 120 分钟后，.ExecuteNonQuery() 向数据库中插入的 100 000 条数据仍然是运行。这很慢。

Answer 1

对于 MysqlDataAdapter，我们只需要设置 selectCommand。它会通过 MySqlCommandBuilder

自动生成 insertCommand

您的代码几乎是正确的，只需更改 2 处。

1.在 dataAdapterCurrentTest.Update(ds.Tables["currentTest"])

之前添加以下行

new MySqlCommandBuilder(dataAdapterCurrentTest);

2。在代码行后面评论

dataAdapterCurrentTest.InsertCommand=insertCmd

所以最后的代码是

 class Program
    {
        static void Main(string[] args)
        {
            MySqlConnectionStringBuilder connBuilder = new MySqlConnectionStringBuilder();

            connBuilder.Server = "ds2";
            connBuilder.Database = "fhem";
            connBuilder.UserID = "fhemdbuser";
            connBuilder.Port = 3307;
            connBuilder.Password = "!2345Abcde";
            //connBuilder.DefaultCommandTimeout = 120;
            //connBuilder.UseDefaultCommandTimeoutForEF = true;
            //connBuilder.AllowUserVariables = true;

            MySqlConnection conn = new MySqlConnection(connBuilder.ConnectionString);
            conn.Open();
            MySqlCommand selectCmdCurrent = new MySqlCommand("select `TIMESTAMP`, `DEVICE`, `TYPE`, `EVENT`, `READING`, `VALUE`, `UNIT` from current;", conn);
            MySqlCommand selectCmdCurrentTest = new MySqlCommand("select `TIMESTAMP`, `DEVICE`, `TYPE`, `EVENT`, `READING`, `VALUE`, `UNIT` from currentTest;", conn);
            MySqlCommand updateCmd = new MySqlCommand("update `currentTest` set `TIMESTAMP`=@p1,`DEVICE`=@p2,`TYPE`=@p3,`EVENT`=@p4,`READING`=@p5,`VALUE`=@p6,`UNIT`=@p7", conn);
            updateCmd.Parameters.Add("@p1", MySql.Data.MySqlClient.MySqlDbType.DateTime);
            updateCmd.Parameters.Add("@p2", MySql.Data.MySqlClient.MySqlDbType.VarString, 128);
            updateCmd.Parameters.Add("@p3", MySql.Data.MySqlClient.MySqlDbType.VarString, 128);
            updateCmd.Parameters.Add("@p4", MySql.Data.MySqlClient.MySqlDbType.VarString, 512);
            updateCmd.Parameters.Add("@p5", MySql.Data.MySqlClient.MySqlDbType.VarString, 128);
            updateCmd.Parameters.Add("@p6", MySql.Data.MySqlClient.MySqlDbType.VarString, 128);
            updateCmd.Parameters.Add("@p7", MySql.Data.MySqlClient.MySqlDbType.VarString, 128);

            MySqlCommand insertCmd = new MySqlCommand("insert into `currentTest` values(@p1, @p2, @p3, @p4, @p5, @p6, @p7)", conn);
            insertCmd.Parameters.Add("@p1", MySql.Data.MySqlClient.MySqlDbType.DateTime);
            insertCmd.Parameters.Add("@p2", MySql.Data.MySqlClient.MySqlDbType.VarString, 128);
            insertCmd.Parameters.Add("@p3", MySql.Data.MySqlClient.MySqlDbType.VarString, 128);
            insertCmd.Parameters.Add("@p4", MySql.Data.MySqlClient.MySqlDbType.VarString, 512);
            insertCmd.Parameters.Add("@p5", MySql.Data.MySqlClient.MySqlDbType.VarString, 128);
            insertCmd.Parameters.Add("@p6", MySql.Data.MySqlClient.MySqlDbType.VarString, 128);
            insertCmd.Parameters.Add("@p7", MySql.Data.MySqlClient.MySqlDbType.VarString, 128);
            MySqlDataAdapter dataAdapterCurrent = new MySqlDataAdapter(selectCmdCurrent);
            MySqlDataAdapter dataAdapterCurrentTest = new MySqlDataAdapter(selectCmdCurrentTest);
            // MySqlCommandBuilder builder = new MySqlCommandBuilder(dataAdapterCurrent);
           // dataAdapterCurrentTest.InsertCommand = insertCmd;
            dataAdapterCurrentTest.UpdateCommand = updateCmd;
            DataSet ds = new DataSet();
            MySqlCommand prepareCmd = new MySqlCommand("truncate currentTest;", conn);
            prepareCmd.ExecuteNonQuery();
            //prepareCmd = new MySqlCommand("insert into currentTest select * from current;", conn);
            //prepareCmd.ExecuteNonQuery();
            prepareCmd = new MySqlCommand("INSERT INTO `currentTest` VALUES(\"2020-06-06 12:45:23\",\"DEVICE\", \"TYPE\", \"EVENT\", \"READING\", \"VALUE\", \"UNIT\")", conn);
            for (int i = 0; i < 10; i++)
                prepareCmd.ExecuteNonQuery();
            dataAdapterCurrentTest.Fill(ds, "currentTest");
            dataAdapterCurrent.Fill(ds, "current");
            int row = 0;

            Stopwatch sw = new Stopwatch();
            for (int i = 0; i < 10; i++)
            {

                DataRow newrow = ds.Tables["currentTest"].NewRow();
                newrow["Timestamp"] = DateTime.Now;
                newrow["Device"] = "Device";
                newrow["TYPE"] = "Type";
                newrow["EVENT"] = "Event";
                newrow["READING"] = "Reading";
                newrow["VALUE"] = "Value";
                newrow["UNIT"] = "Unit";
                ds.Tables["currentTest"].Rows.Add(newrow);
            }

            new MySqlCommandBuilder(dataAdapterCurrentTest);

            dataAdapterCurrentTest.Update(ds.Tables["currentTest"]);
            ds.Tables["currentTest"].AcceptChanges();
        }
    }

将值插入 mysql 数据库未按预期工作

Inserting values into a mysql database does not work as expected

c#

mysql

dataadapter