一) 前置条件：

(1)       Linux 已经安装好 mysql 数据库；

(2)       Linux 已经安装了 gcc 编译器；

(二)数据库准备：

为了便于描述，假设数据库的 root 用户密码为 root_pwd 。

(1)       以 root 用户登陆数据库

#mysql -uroot –proot_pwd

mysql>

(2)       创建数据 testdb

mysql> create database testdb;

(3)       创建表

mysql> use testdb;

mysql> create table t_users(userid int not null, username varchar(20) not null);

(4)       向表中插入一条记录

mysql> insert into t_users(userid, username) values(1, 'HuDennis');

(5)       创建用户

mysql> create user testdb_user;

(6)       对用户授权

mysql> grant select, insert, update, delete on *.* to 'testdb_user'@'localhost' identified by '123456';

mysql> flush privileges;

(7)       查看用户及该用户的权限

mysql> use mysql;

mysql> select user from user;

mysql> show grants for testdb_user@localhost;

(8)       [ 备用 ] 删除数据库及用户

mysql> drop database testdb;

mysql> show databases;

mysql> drop user testdb_user;

mysql> drop user testdb_user@localhost;

(三) C 源代码 testdb.c 准备：

#include

#include

#include

static char *server_options[] = { "mysql_test", "--defaults-file=my.cnf" };

int num_elements = sizeof(server_options)/ sizeof(char *);

static char *server_groups[] = { "libmysqld_server", "libmysqld_client" };

int main(void)

{

if (mysql_server_init(num_elements, server_options, server_groups))

{

exit(1);

}

MYSQL *conn;

MYSQL_RES *res;

MYSQL_ROW row;

char *server = "localhost";

char *user = "testdb_user";

char *password = "123456";

char *database = "testdb";

conn = mysql_init(NULL);

/* Connect to database */

if (!mysql_real_connect(conn, server,

user, password, database, 0, NULL, 0))

{

fprintf(stderr, "%s/n", mysql_error(conn));

exit(1);

}

/* send SQL query */

if (mysql_query(conn, "select userid, username from t_users"))

{

fprintf(stderr, "%s/n", mysql_error(conn));

exit(1);

}

if ((res = mysql_use_result(conn)) == NULL)

{

fprintf(stderr, "%s/n", mysql_error(conn));

exit(1);

}

int num = mysql_num_fields(res);

while ((row = mysql_fetch_row(res)) != NULL)

{

int i=0;

for (; i

{

printf("%s ", row[i]);

}

printf("/n");

}

/* close connection */

mysql_free_result(res);

mysql_close(conn);

/* Use any MySQL API functions here */

mysql_server_end();

return EXIT_SUCCESS;

}#include #include #include static char *server_options[] = { "mysql_test", "--defaults-file=my.cnf" };int num_elements = sizeof(server_options)/ sizeof(char *); static char *server_groups[] = { "libmysqld_server", "libmysqld_client" }; int main(void){ if (mysql_server_init(num_elements, server_options, server_groups)) { exit(1); } MYSQL *conn; MYSQL_RES *res; MYSQL_ROW row; char *server = "localhost"; char *user = "testdb_user"; char *password = "123456"; char *database = "testdb"; conn = mysql_init(NULL); /* Connect to database */ if (!mysql_real_connect(conn, server, user, password, database, 0, NULL, 0)) { fprintf(stderr, "%s/n", mysql_error(conn)); exit(1); } /* send SQL query */ if (mysql_query(conn, "select userid, username from t_users")) { fprintf(stderr, "%s/n", mysql_error(conn)); exit(1); } if ((res = mysql_use_result(conn)) == NULL) { fprintf(stderr, "%s/n", mysql_error(conn)); exit(1); } int num = mysql_num_fields(res);while ((row = mysql_fetch_row(res)) != NULL) { int i=0; for (; i

(四) C 程序编译与运行：

(1) 编译 testdb.c

# gcc testdb.c -I/usr/local/mysql/include -L/usr/local/mysql/lib -lmysqlclient

注意： -I 和 -L 的路径应该根据 mysql 的安装路径不同而应该有所不同。同理，下面的 LD_LIBRARY_PATH 变量一样。

(2) 将库文件路径加入到 LD_LIBRARY_PATH 环境变量中去

# LD_LIBRARY_PATH =$LD_LIBRARY_PATH:/usr/local/mysql/lib

(3) 运行编译得到的可执行文件 a.out

#./a.out

1 HuDennis