Linux 下用C语言API连接MySQL数据库_MySQL
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像PHP和perl一样,MySQL也提供的C语言使用的API.
C代码的API是随MySQL一起发布的. 它包含在mysqlclient库中, 可以使C程序来访问数据库.
MySQL源码包中的许多客户端都是用C写的. 如果你正在找使用这些C API的例子, 可以看看客户端的写法.你可以在MySQL源码包的clients目录找到这些例子.
软件包
请确保你已经安装了必要的开发环境,比如gcc, mysql等等. 下面是编译一个程序所需要安装的软件包的列表 (Ubuntu为例):
mysql-client
libmysqlclient15-dev和libmysqlclient15off
mysql-server:
gcc, make and other development libs
例子
下面这个例子,连接本机的MySQL服务器,然后列出mysql数据库中所有的表:
以下是引用片段:
QUOTE:
/* Simple C program that connects to MySQL Database server*/
#include
#include
main() {
MYSQL *conn;
MYSQL_RES *res;
MYSQL_ROW row;
char *server = "localhost";
char *user = "root";
char *password = ""; /* 此处改成你的密码 */
char *database = "mysql";
conn = mysql_init(NULL);
/* Connect to database */
if (!mysql_real_connect(conn, server,
user, password, database, 0, NULL, 0)) {
fprintf(stderr, "%s", mysql_error(conn));
exit(1);
}
/* send SQL query */
if (mysql_query(conn, "show tables")) {
fprintf(stderr, "%s", mysql_error(conn));
exit(1);
}
res = mysql_use_result(conn);
/* output table name */
printf("MySQL Tables in mysql database:");
while ((row = mysql_fetch_row(res)) != NULL)
printf("%s ", row[0]);
/* close connection */
mysql_free_result(res);
mysql_close(conn);
}
编译和连接程序
MySQL中有一个特殊的脚本,叫做mysql_config. 它会为你编译MySQL客户端,并连接到MySQL服务器提供有用的信息.你需要使用下面两个选项.
1. --libs 选项 - 连接MySQL客户端函数库所需要的库和选项.
$ mysql_config --libs
输出:
-L/usr/lib64/mysql -lmysqlclient -lz -lcrypt -lnsl -lm -L/usr/lib64 -lssl -lcrypto
2. --cflags 选项 - 使用必要的include文件的选项等等.
$ mysql_config --cflags
输出:
-I/usr/include/mysql -g -pipe -m64 -D_GNU_SOURCE -D_FILE_OFFSET_BITS=64 -D_LARGEFILE_SOURCE -fno-strict-aliasing
你需要将上面两个选项加入到对源文件的编译命令中. 所以,要编译上面的程序,要使用下面的命令:
$ gcc -o output-file $(mysql_config --cflags) mysql-c-api.c $(mysql_config --libs)
执行编译后的程序:
$ ./output.filebitsCN.com

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