Transaction Concepts for Getting Started with MySQL

MYSQL automatically submits by default, that is, if you submit a QUERY, it will be executed directly! We can disable automatic submission by
set autocommit=0
set autocommit=1 to enable automatic submission
Only the INNODB engine in mysql supports transaction processing, and the default is automatic submission;
Another commonly used MYISAM The engine does not support transactions and has no concept of transactions.

It can be compared to the concept of Oracle transactions! ! !

You can avoid MySQL's automatic submission and encapsulate the API yourself to implement rollback and other operations! ! !

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <dlfcn.h>
#include <mysql/mysql.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include <termios.h>
#include <mysql/mysql.h>
/*
MySQL set autocommit = 0或1分别什么啊,哪个是自动提交啊
要熟练使用mysql的帮助文档，在里面查找autocommit，就会有相应的注释，比我在这里直接给你说要深刻得多。
autocoomit是事务，根据mysql的文档如果等于1是立即提交。但在transction中只有遇到commit或rollback才提交。希望对你有用。
*/
/*
MYSQL默认是自动提交的，也就是你提交一个QUERY，它就直接执行！我们可以通过
     set autocommit=0  禁止自动提交
     set autocommit=1 开启自动提交 
mysql中INNODB引擎才支持事务处理，默认是自动提交的；
另外一种常用的MYISAM引擎是不支持事务的，本身就没有事务的概念 
*/
#define BEGIN_TRAN      "START TRANSACTION"
#define SET_TRAN            "SET AUTOCOMMIT=0"  
#define UNSET_TRAN      "SET AUTOCOMMIT=1"
#define COMMIT_TRAN     "COMMIT"
#define ROLLBACK_TRAN   "ROLLBACK"
int mysql_BeginTran(MYSQL *mysql)
{
    int ret = 0;
    //--执行事务开始SQL
    ret = mysql_query(mysql, BEGIN_TRAN);
    if (ret != 0)
    {
        printf("func mysql_query() err: %d\n", ret);
        return ret;
    }
    //--设置事务手动提交
    ret = mysql_query(mysql, SET_TRAN);
    if (ret != 0)
    {
        printf("func mysql_query() err: %d\n", ret);
        return ret;
    }
    return ret;
}
int mysql_Rollback(MYSQL *mysql)
{
    int ret = 0;
    //--事务回滚操作
    ret = mysql_query(mysql, ROLLBACK_TRAN);
    if (ret != 0)
    {
        printf("func mysql_query() err: %d\n", ret);
        return ret;
    }
    //--恢复事务自动提交标志
    ret = mysql_query(mysql, UNSET_TRAN);
    if (ret != 0)
    {
        printf("func mysql_query() err: %d\n", ret);
        return ret;
    }
    return ret;
}
int mysql_Commit(MYSQL *mysql)
{
    int ret = 0;
    //--执行事务提交SQL
    ret = mysql_query(mysql, COMMIT_TRAN);
    if (ret != 0)
    {
        printf("func mysql_query() err: %d\n", ret);
        return ret;
    }
    //--恢复自动提交设置
    ret = mysql_query(mysql, UNSET_TRAN);
    if (ret != 0)
    {
        printf("func mysql_query() err: %d\n", ret);
        return ret;
    }
    return ret;
}
// 建表 create table test_table(col1 int, col2 varchar(10), col3 varchar(10)); 
#define sql01 "INSERT INTO test_table(col1,col2,col3) VALUES(10, &#39;10&#39;, &#39;1&#39;)"
#define sql02 "INSERT INTO test_table(col1,col2,col3) VALUES(20, &#39;20&#39;, &#39;2&#39;)"
#define sql03 "INSERT INTO test_table(col1,col2,col3) VALUES(30, &#39;30&#39;, &#39;3&#39;)"
#define sql04 "INSERT INTO test_table(col1,col2,col3) VALUES(40, &#39;40&#39;, &#39;4&#39;)"
int main()
{
    int         ret = NULL;
    MYSQL       *mysql;
    MYSQL_RES   *res;
    MYSQL_ROW   row;
    char        *query;
    mysql = mysql_init(NULL);
    mysql =mysql_real_connect(mysql, "localhost", "root", "123456", "mydb2", 0, NULL, 0 );
    if (mysql == NULL)
    {
        ret = mysql_errno(mysql);
        printf("func mysql_real_connect() err\n");
        return ret;
    }
    else
    {
        printf(" ok......\n");
    }
    ret = mysql_BeginTran(mysql);
    if (ret != 0)
    {
        printf("mysql_BeginTran() err:%d\n", ret);
        return ret;
    }
    ret = mysql_query(mysql, sql01);
    if (ret != 0)
    {
        printf("mysql_query() err:%d\n", ret);
        return ret;
    }
    ret = mysql_query(mysql, sql02);
    if (ret != 0)
    {
        printf("mysql_query() err:%d\n", ret);
        return ret;
    }
    ret = mysql_Commit(mysql);
    if (ret != 0)
    {
        printf("mysql_Commit() err:%d\n", ret);
        return ret;
    }
    ret = mysql_BeginTran(mysql);
    if (ret != 0)
    {
        printf("mysql_BeginTran() err:%d\n", ret);
        return ret;
    }
    ret = mysql_query(mysql, sql03);
    if (ret != 0)
    {
        printf("mysql_query() err:%d\n", ret);
        return ret;
    }
    ret = mysql_query(mysql, sql04);
    if (ret != 0)
    {
        printf("mysql_query() err:%d\n", ret);
        return ret;
    }
    ret = mysql_Rollback(mysql);
    if (ret != 0)
    {
        printf("mysql_Rollback() err:%d\n", ret);
        return ret;
    }
    mysql_close(mysql);
}

The above is the content of the transaction concept for getting started with MySQL. For more related content, please pay attention to the PHP Chinese website (www.php.cn)!