Linux下通过C语言操作MySQL数据库

实验环境：

Fedora 11

组件：

libdbi-dbd-mysql-0.8.3-4.fc11.i586

mysql-5.1.42-2.fc11.i586

mysql-libs-5.1.42-2.fc11.i586

mysql-devel-5.1.42-2.fc11.i586

mysql-connector-java-5.1.8-2.fc11.i586

qt-mysql-4.5.3-9.fc11.i586

php-mysql-5.2.11-2.fc11.i586

mysql-connector-odbc-5.1.5r1144-4.fc11.i586

mysql-server-5.1.42-2.fc11.i586

第一步：

启动一个mysql客户端

[mtd@mutiandong mysql]$ mysql -u root -p

Enter password:

Welcome to the MySQL monitor. Commands end with ; or \g.

Your MySQL connection id is 20

Server version: 5.1.42 Source distribution

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql>

创建一个数据库

mysql> create database cusemysql;

Query OK, 1 row affected (0.00 sec)

并使用这个数据库

mysql> use cusemysql;

Database changed

在给数据库内创建一个表

mysql> create table children(childno int not null unique,fname varchar(20),age int);

Query OK, 0 rows affected (0.00 sec)

在该表内插入一项数据

mysql> insert into children values(5,‘jhon’,10);

Query OK, 1 row affected (0.00 sec)

mysql> select * from children;

+---------+-------+------+

| childno | fname | age |

+---------+-------+------+

| 1 | jhon | 10 |

+---------+-------+------+

1 row in set (0.00 sec)

mysql>

第二部：

编写 insert.c

///////////////////////////////////

/* insert.c */

#include

#include

#include

/*注意哦，上面写的是mysql.h的绝对地址，一般在/usr/include/mysql下，仔细看看你的在哪里？这种方式 #include "mysql/h" 可能也可以*/

int main(int argc, char *argv[])

{

MYSQL my_connection;

int res;

mysql_init(&my_connection);

/*mysql_real_connect(&mysql,主机名,用户名,密码,数据库名,0,NULL,0) == NULL)*/

/*mysql_real_connect(&mysql,host,user,passwd,dbname,0,NULL,0) == NULL)*/

if (mysql_real_connect(&my_connection, "localhost", "root", "","cusemysql",0,NULL,CLIENT_FOUND_ROWS))

{

printf("Connection success\n");

res = mysql_query(&my_connection, "insert into children values(11,'Anny',5)");

if (!res)

{

printf("Inserted %lu rows\n",(unsigned long)mysql_affected_rows(&my_connection));

/*里头的函数返回受表中影响的行数*/

}

else

{

//分别打印出错误代码及详细信息

fprintf(stderr, "Insert error %d: %s\n",mysql_errno(&my_connection),mysql_error(&my_connection));

}

mysql_close(&my_connection);

}

else

{

fprintf(stderr, "Connection failed\n");

if (mysql_errno(&my_connection))

{

fprintf(stderr, "Connection error %d: %s\n",mysql_errno(&my_connection),mysql_error(&my_connection));

}

}

return EXIT_SUCCESS;

}

/////////////////////////////////////////////

代码写完了，要编译哦

[mtd@mutiandong mysql]# gcc -o insert insert.c

/tmp/ccyHfsX2.o(.text+0x1e): In function `main':

: undefined reference to `mysql_init'

/tmp/ccyHfsX2.o(.text+0x47): In function `main':

: undefined reference to `mysql_real_connect'

/tmp/ccyHfsX2.o(.text+0x76): In function `main':

: undefined reference to `mysql_query'

/tmp/ccyHfsX2.o(.text+0x9a): In function `main':

: undefined reference to `mysql_affected_rows'

/tmp/ccyHfsX2.o(.text+0xbc): In function `main':

: undefined reference to `mysql_error'

/tmp/ccyHfsX2.o(.text+0xcf): In function `main':

: undefined reference to `mysql_errno'

/tmp/ccyHfsX2.o(.text+0xf5): In function `main':

: undefined reference to `mysql_close'

/tmp/ccyHfsX2.o(.text+0x11f): In function `main':

: undefined reference to `mysql_errno'

/tmp/ccyHfsX2.o(.text+0x135): In function `main':

: undefined reference to `mysql_error'

/tmp/ccyHfsX2.o(.text+0x148): In function `main':

: undefined reference to `mysql_errno'

collect2: ld returned 1 exit status

[mtd@mutiandong mysql]#

头文件和库文件位置没有指定

[mtd@mutiandong mysql]# gcc -o insert insert.c -I/usr/include/mysql/ -L/usr/lib/mysql/

/tmp/cc4gdmlp.o(.text+0x1e): In function `main':

: undefined reference to `mysql_init'

/tmp/cc4gdmlp.o(.text+0x47): In function `main':

: undefined reference to `mysql_real_connect'

/tmp/cc4gdmlp.o(.text+0x76): In function `main':

: undefined reference to `mysql_query'

/tmp/cc4gdmlp.o(.text+0x9a): In function `main':

: undefined reference to `mysql_affected_rows'

/tmp/cc4gdmlp.o(.text+0xbc): In function `main':

: undefined reference to `mysql_error'

/tmp/cc4gdmlp.o(.text+0xcf): In function `main':

: undefined reference to `mysql_errno'

/tmp/cc4gdmlp.o(.text+0xf5): In function `main':

: undefined reference to `mysql_close'

/tmp/cc4gdmlp.o(.text+0x11f): In function `main':

: undefined reference to `mysql_errno'

/tmp/cc4gdmlp.o(.text+0x135): In function `main':

: undefined reference to `mysql_error'

/tmp/cc4gdmlp.o(.text+0x148): In function `main':

: undefined reference to `mysql_errno'

collect2: ld returned 1 exit status

[mtd@mutiandong mysql]#

gcc还是找不到头文件，下面我们可以这样,指定gcc专门找 mysqlclient 之类的库

[root@localhost testmysql]# gcc -o insert insert.c -lmysqlclient -I/usr/include/mysql/ -L/usrlib/mysql

我用 -lmysqlclient 选项就可以了。

ok,现在我们执行看看

[mtd@mutiandong mysql]# ./insert

Connection Success

Inserted 1 rows

呵呵，真的成功了！

不信到mysql下看看表children中是否多了刚才插入的那一行数据

mysql> select * from children;

+---------+-------+------+

| childno | fname | age |

+---------+-------+------+

| 1 | jhon | 10 |

| 11 | Anny | 5 |

+---------+-------+------+

2 rows in set (0.00 sec)