MySQL中的C API
#include my_global.h#include mysql.hint main(int argc, char **argv){ MYSQL *conn; MYSQL_RES *result; MYSQL_ROW row; int num_fields; int i; conn = mysql_init(NULL); mysql_real_connect(conn, localhost, user, passwd, test, 0, NULL, 0); mysql_
#include <my_global.h> #include <mysql.h> int main(int argc, char **argv) { MYSQL *conn; MYSQL_RES *result; MYSQL_ROW row; int num_fields; int i; conn = mysql_init(NULL); mysql_real_connect(conn, "localhost", "user", "passwd", "test", 0, NULL, 0); mysql_query(conn, "select * from student"); result = mysql_store_result(conn); num_fields = mysql_num_fields(result); while ((row = mysql_fetch_row(result))) { for(i = 0; i <br> 注释: <p>MYSQL* conn;</p> conn = mysql_init(NULL);<br> 初始化一个MYSQL结构体,这个结构体就是一个数据库连接句柄。<br> <p><br> </p> <p>mysql_real_connect(conn, "localhost", "user", '"passwd", "test", 0, NULL, 0) ;<br> </p> <p>建立一个到mysql数据库的链接。函数参数 链接句柄、主机名、用户、密码、数据库名、端口、unix套接字和客户端标志。<br> </p> <p><br> </p> <p>mysql_query(conn, "create database testdb");</p> <p>mysql_query执行指定为“以Null终结的字符串”的SQL查询。<br> </p> <p><br> </p> <p>MYSQL_RES *result;<br> </p> <p>result = mysql_store_result(conn);<br> </p> <p>检索完整的结果集至客户端。<br> </p> <p><br> </p> <p>MYSQL_ROW row;</p> <p>row = mysql_fetch_row(result)<br> </p> <p>获取结果集中的一行</p> <p> </p> <p>mysql_num_fields(result);<br> </p> <p>返回结果集中的列数</p> <p><br> </p> <p>for(i = 0; i </p> <p>printf("%s ", row[i] ? row[i] : "NULL");</p> <p>}<br> </p> <p>输出一行数据</p> <p><br> </p> <p>mysql_close(conn);<br> <br> 关闭数据库链接。<br> </p> <p><br> </p> <p>printf("Error %u: %s\n", mysql_errno(conn), mysql_error(conn));<br> </p> <p>错误处理。mysql_errno返回上次调用的MySQL函数的错误编号。</p> <p>mysql_error返回上次调用的MySQL函数的错误消息。</p> <p><br> </p> <p>除非作了其他规定,返回指针的函数将返回非Null值,以指明成功,或返回NULL值以指明出错。</p> <p>返回整数的函数将返回0以指明成功,或返回非0值以指明出错。注意,非0值仅表明这点。</p> <p>除非在函数描述中作了其他说明,不要对非0值进行测试:<br> if (result) /* correct */<br> ... error ...</p> <p><br> if (result ... error ...<br> <br> if (result == -1) /* incorrect */<br> </p> <p><br> </p> <p><br> </p> </mysql.h></my_global.h>

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