[C # MySQL] It took more than two hours to use C # For MySQL operations for the first time. Finally, C # was successfully used to complete MySQL operations, query, modify, and delete, I don't know whether to be happy or sad (it took two hours). In short, it is necessary to write down some experience to prevent the same detours in the future: the SQL statement is very important.
[C # MySQL] It took more than two hours to use C # For MySQL operations for the first time. Finally, C # was successfully used to complete MySQL operations, query, modify, and delete, I don't know whether to be happy or sad (it took two hours). In short, it is necessary to write down some experience to prevent the same detours in the future: the SQL statement is very important.
[C # MySQL] the first time I used C # To operate MySQL
It took more than two hours to successfully use C # To complete MySQL operations, query, modify, and delete, still sad (it took two hours). In short, it is necessary to write down some experience to prevent the same detours in the future:
- The format of an SQL statement is very important. For example, the Table name should use the 'table' symbol, which is not a regular single quotation mark. If you are not sure how to extract it, we recommend that you use the MySQL graphical tool (such as phpMyAdmin) to automatically generate it, then copy, for example: string SQL = "SELECT * FROM '000000' WHERE 'pics id' LIKE 'a. 4.1-1/1 '";" insert into 'picsdic '. '123' ('pics id', 'pics description', 'ref. ', 'release', 'mnemonic', 'comments') VALUES ('a. 1/2 ', 'test'); "string sqlDelete =" delete from 'picsdic '. '20180101' WHERE '20180101 '. 'pics id' = 'a. 1/3 '";
- You do not need to export the search on the internet blindly. First, read the official documents carefully. Many times, the official documents are translated on the internet, and they are not comprehensive.
- MSDN and ConnectorNET. chm have helped a lot, at least more reliable than the information on the Internet.
using System;using System.Data;using System.Configuration;using System.Collections;using System.Web;using System.Web.Security;using System.Web.UI;using System.Web.UI.WebControls;using System.Web.UI.WebControls.WebParts;using System.Web.UI.HtmlControls;using MySql.Data.MySqlClient;namespace MySQLConnection{ public partial class _Default : System.Web.UI.Page { protected void Page_Load(object sender, EventArgs e) { string connStr = "server=127.1.1.1;user=root;database=PICSDic;port=3306;password=HONGXING;"; MySqlConnection conn = new MySqlConnection(connStr); try { //Console.WriteLine("Connecting to MySQL..."); Label1.Text = "Connecting to MySQL..."; conn.Open(); // Perform database operations //Query string sql = "SELECT * FROM `365232` WHERE `PICS ID` LIKE 'A.4.1-1/1'"; MySqlCommand cmd = new MySqlCommand(sql, conn); MySqlDataReader rdr = cmd.ExecuteReader(); while (rdr.Read()) { txt1.Text = rdr[0] + " -- " + rdr[1]; } rdr.Close(); //Insert string sqlInsert = "INSERT INTO `picsdic`.`365232` (`PICS ID` ,`PICS Description` ,`Ref.` ,`Release` ,`Mnemonic` ,`Comments`)VALUES ('A.1/3', 'test', 'test', 'test', 'test', 'test');"; MySqlCommand cmdInsert = new MySqlCommand(sqlInsert, conn); cmdInsert.ExecuteNonQuery(); //Delete //string sqlDelete = "DELETE FROM `picsdic`.`365232` WHERE `365232`.`PICS ID` = 'A.1/2' AND `365232`.`PICS Description` = 'test' AND `365232`.`Ref.` = 'test' AND `365232`.`Release` = 'test' AND `365232`.`Mnemonic` = 'test' AND `365232`.`Comments` = 'test' LIMIT 1"; string sqlDelete = "DELETE FROM `picsdic`.`365232` WHERE `365232`.`PICS ID` = 'A.1/3'"; MySqlCommand cmdDelete = new MySqlCommand(sqlDelete, conn); cmdDelete.ExecuteNonQuery(); }