使用mysql的c++API实现增删改查操作

 写在前面

        简单地在vs中实现了一下对于mysql的增删改查的实现内容，感觉最重要的一句话api为：

int STDCALL mysql_query(MYSQL *mysql, const char *q);

 所有的语句的实现都是经过这一语句！后面的api的参考博客值得收藏！

程序

//初始化
bool ConnectDatabase(MYSQL &mysql)
{
	mysql_init(&mysql);

	if (!mysql_real_connect(&mysql, "localhost", "root", "password", "database name", 3306, NULL
		, 0)) {
		printf("Error connecting to database:%s\n", mysql_error(&mysql));
		return false;
	}
	else {
		mysql_query(&mysql, "set names gbk");
		printf("Connected..\n");
		return true;
	}
}

//插入数据函数
bool InsertData(MYSQL& mysql,const char *s1,const  char *s2, float f1, float f2, float f3, float f4)
{
	char insertsql[1024];
	int len = sprintf_s(insertsql, 256, "INSERT INTO table_name values ('%s','%s',%f,%f,%f,%f);", s1, s2, f1, f2, f3, f4);
	printf("%s\n", insertsql);
	if (len < 0) {
		printf("Insert data failed!\n");
		return false;
	}
	if (mysql_query(&mysql, insertsql) == 0) {
		printf("Insert data success!\n");
		return true;
	}
	else {
		printf("Insert failed (%s)\n", mysql_error(&mysql));
		return false;
	}
}
//选择函数
//没有where的情况
bool SelectData(MYSQL &mysql, const char *columns_name,const char *table_name)
{
	char querysql[1024];
	int len = sprintf_s(querysql, 256, "SELECT %s FROM %s;", columns_name, table_name);
	printf("%s\n", querysql);
	if (len < 0) {
		printf("Select data failed!\n");
		return false;
	}
	if (mysql_query(&mysql, querysql) == 0) {
		printf("Select data success!\n");
	}
	else {
		printf("Select failed (%s)\n", mysql_error(&mysql));
		return false;
	}
	MYSQL_RES *res;             //返回行的查询结果集
	MYSQL_FIELD *fd;            //字段列数组
	MYSQL_ROW column;
	char field[32][32];

	//查询返回的数据
	res = mysql_store_result(&mysql);

	//打印数据行数
	printf("number of dataline returned:%d\n", mysql_affected_rows(&mysql));
	//获取列数
	int column_num = mysql_num_fields(res);
	//输出选择完的列名称
	for (int i = 0; fd = mysql_fetch_field(res); i++)
		strcpy_s(field[i], strlen(fd->name) + 1, fd->name);

	for (int i = 0; i < column_num; i++)
		printf("%10s\t", field[i]);
	printf("\n");
	//输出每一行的数据
	while (column = mysql_fetch_row(res))
	{
		for (int i = 0; i < column_num; i++)
			printf("%10s\t", column[i]);
		printf("\n");
	}
	return true;
}

/*
重载有where的情况
*/
bool SelectData(MYSQL &mysql, const char *columns_name, const char *table_name, const char *limited_info)
{
	char querysql[1024];
	int len = sprintf_s(querysql, 256, "SELECT %s FROM %s WHERE %s;", columns_name, table_name, limited_info);
	printf("%s\n", querysql);
	if (len < 0) {
		printf("Select data failed!\n");
		return false;
	}
	if (mysql_query(&mysql, querysql) == 0) {
		printf("Select data success!\n");
	}
	else {
		printf("Select failed (%s)\n", mysql_error(&mysql));
		return false;
	} 
	MYSQL_RES *res;             //返回行的查询结果集
	MYSQL_FIELD *fd;            //字段列数组
	MYSQL_ROW column;
	char field[32][32];

	//查询返回的数据
	res = mysql_store_result(&mysql);                         
	
	//打印数据行数
	printf("number of dataline returned:%d\n", mysql_affected_rows(&mysql));
	//获取列数
	int column_num = mysql_num_fields(res);                  
	//输出选择完的列名称
	for (int i = 0; fd = mysql_fetch_field(res); i++)
		strcpy_s(field[i], strlen(fd->name) + 1, fd->name);

	for (int i = 0; i < column_num; i++)
		printf("%10s\t", field[i]);
	printf("\n");
	//输出每一行的数据
	while (column = mysql_fetch_row(res))                                  //返回结果集中的下一行
	{
		for (int i = 0; i < column_num; i++)
			printf("%10s\t", column[i]);
		printf("\n");
	}
	return true;
}

//修改操作
bool UpdateData(MYSQL &mysql, const char *table_name, const char *modified_info, const char *limitde_info)
{
	char updatesql[1024];
	int len = sprintf_s(updatesql, 256, "UPDATE %s SET %s WHERE %s;", table_name, modified_info, limitde_info);
	printf("%s\n", updatesql);
	if (len < 0) {
		printf("Update data failed!\n");
		return false;
	}
	if (mysql_query(&mysql, updatesql) == 0) {
		printf("Update data success!\n");
		return true;
	}
	else {
		printf("Update failed (%s)\n", mysql_error(&mysql));
		return false;
	}
}

//删除数据函数
bool DeleteData(MYSQL &mysql, const char *table_name, const char *limited_info)
{
	char deletesql[1024];
	int len = sprintf_s(deletesql, 256, "DELETE FROM %s WHERE %s;", table_name, limited_info);
	printf("%s\n", deletesql);
	if (len < 0) {
		printf("Delete data failed!\n");
		return false;
	}
	if (mysql_query(&mysql, deletesql) == 0) {
		printf("Delete data success!\n");
		return true;
	}
	else {
		printf("Delete failed (%s)\n", mysql_error(&mysql));
		return false;
	}
}

参考博客

程序参考：https://www.cnblogs.com/47088845/p/5706496.html

api参考：https://blog.csdn.net/lynnucas/article/details/49430039