linux下的mysql的C编程，需要安装mysql及mysql的开发包

要进行linux下的mysql的C编程，需要安装mysql及mysql的开发包，ubuntu下直接apt-get install libmysql++安装开发包。

#include <mysql.h>

相关函数:

MYSQL *mysql_init(MYSQL *); //这里称之为载入函数吧，返回的MYSQL指针要用到后续的函数中 int mysql_options(MYSQL *connection, enum option_to_set,const char *argument); //设置MYSQL*的一些属性，比如超时时间等  MYSQL *mysql_real_connect(MYSQL *connection, const char *server_host, const char *sql_user_name, const char *sql_password, const char *db_name,
                unsigned int port_number,//置0连接默认端口，一般为3306 const char *unix_socket_name,//NULL unsigned int flags);//无另外属性时置0 //连接函数 void mysql_close(MYSQL *connection); //关闭连接  unsigned int mysql_errno(MYSQL *connection); //返回错误代码 char *mysql_error(MYSQL *connection); //返回错误信息 int mysql_query(MYSQL *connection, const char *query); //执行sql语句  my_ulonglong mysql_affected_rows(MYSQL *connection); //返回执行语句过后受影响的行数  MYSQL_RES *mysql_store_result(MYSQL *connection); //返回执行结果，适用于数据量较小时  my_ulonglong mysql_num_rows(MYSQL_RES *result); //返回上面函数返回结果的行数  MYSQL_ROW mysql_fetch_row(MYSQL_RES *result); //抽取一条记录，返回NULL时表示抽取完记录或者错误 void mysql_data_seek(MYSQL_RES *result, my_ulonglong offset); //调整数据位置，offset为0时，下次调用mysql_fetch_row将返回result第一条记录  MYSQL_ROW_OFFSET mysql_row_tell(MYSQL_RES *result); //返回当前的位置  MYSQL_ROW_OFFSET mysql_row_seek(MYSQL_RES *result, MYSQL_ROW_OFFSET offset); //移动数据位置，并返回先前的位置，可以和上一个函数结合使用 void mysql_free_result(MYSQL_RES *result); //释放result空间  MYSQL_RES *mysql_use_result(MYSQL *connection); //返回执行结果，适用于数据量较大时  unsigned int mysql_field_count(MYSQL *connection); //返回查询结果中的列数（column数）  MYSQL_FIELD *mysql_fetch_field(MYSQL_RES *result); //获得查询结果中的列名等信息（表头信息）

例子：

创建测试数据库
mysql> create database test;
创建用户
mysql> grant all on test.* to test@'localhost' identified by 'test';

sql文件：

--
-- Create the table children -- CREATE TABLE children (
childno int(11) NOT NULL auto_increment,
fname varchar(30),
age int(11), PRIMARY KEY (childno)
); --
-- Populate the table ‘children’ --  INSERT INTO children(childno,fname,age) VALUES(1,'Jenny',21); INSERT INTO children(childno,fname,age) VALUES(2,'Andrew',17); INSERT INTO children(childno,fname,age) VALUES(3,'Gavin',8); INSERT INTO children(childno,fname,age) VALUES(4,'Duncan',6); INSERT INTO children(childno,fname,age) VALUES(5,'Emma',4); INSERT INTO children(childno,fname,age) VALUES(6,'Alex',15); INSERT INTO children(childno,fname,age) VALUES(7,'Adrian',9);

	

		C代码:
	

	

		
		

			
		

#include <stdio.h> #include <stdlib.h> #include <mysql.h> MYSQL *mysql_main;
MYSQL_RES *res_ptr;
MYSQL_ROW sqlrow; void display_header(); void display_row(); int main(int argc,char *argv[])
{ int res; int first_row = 1;

    mysql_main = mysql_init(NULL); if(!mysql_main)
    {
        fprintf(stderr,"mysql_init failed\n"); return EXIT_FAILURE;
    }
    mysql_main = mysql_real_connect(mysql_main,"localhost","test","test","test",0,NULL,0); if(mysql_main)
    {
        printf("Connection success:\n");
        res = mysql_query(mysql_main,"SELECT childno,fname,age FROM children WHERE age>5"); if(res)
        {
            fprintf(stderr,"SELECT error: %s\n",mysql_error(mysql_main));
        } else {
            res_ptr = mysql_use_result(mysql_main); if(res_ptr)
            { while((sqlrow = mysql_fetch_row(res_ptr)))
                { if(first_row)
                    {
                        display_header();
                        first_row = 0;
                    }
                    display_row();
                }
            }
        }
    } else {
        printf("Connection failed\n");
    }
    mysql_close(mysql_main); return EXIT_SUCCESS;
} void display_header()
{
    MYSQL_FIELD *field_ptr;
    printf("Column details:\n"); while((field_ptr = mysql_fetch_field(res_ptr))!=NULL)
    {
        printf("\t Name: %s\n",field_ptr->name);
        printf("\t Type: "); if(IS_NUM(field_ptr->type))
        {
            printf("Numeric filed\n");
        } else { switch(field_ptr->type)
            { case FIELD_TYPE_VAR_STRING:
                printf("VARCHAR\n"); break; case FIELD_TYPE_LONG:
                printf("LONG\n"); break; default:
                printf("Type is %d,check in mysql_com.h\n",field_ptr->type);
            }
        }
        printf("\t MAX width %ld\n",field_ptr->length); if(field_ptr->flags&AUTO_INCREMENT_FLAG)
            printf("\t Auto increments\n");
        printf("\n");
    }
} void display_row()
{
    unsigned int field_count;

    field_count = 0; while(field_count<mysql_field_count(mysql_main))
    { if(sqlrow[field_count]) printf("%s ",sqlrow[field_count]); else printf("NULL");
        field_count++;
    }
    printf("\n");
}
		

			
		
	
	

		gcc -I/usr/include/mysql -L/usr/lib/mysql -lmysqlclient -o mysqltest mysqltest.c
	
	

		./test
	
	

		结果如下：
	
	

		Connection success:

Column details:

Name: childno

Type: Numeric filed

MAX width 11

Auto increments
	
	

		Name: fname

Type: VARCHAR

MAX width 30
	
	

		Name: age

Type: Numeric filed

MAX width 11
	
	

		1 Jenny 21 

2 Andrew 17 

3 Gavin 8 

4 Duncan 6 

6 Alex 15 

7 Adrian 9