MySQL入門之簡單數據查詢

mysql_init初始化數據庫鏈接–得到一個鏈接 mysql_real_connect連接數據庫服務器 執行mysql_query查詢–查詢語句是一個字符串 對每一行分別進行檢索mysql_store_result–結果存儲在鏈接里面,屬于一次性查詢 從結果集,獲取表頭信息–mysql_fetch_fields–表頭信息存儲在mysql_field類型的指針指向的內存空間 解析表頭–mysql_field_count獲取列數,for循環逐列解析 mysql_fetch_row從結果集中一行一行的獲取數據,在針對每一行解析每一列 釋放內存空間

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具體代碼

#include?<stdio.h>  #include?<stdlib.h>  #include?<string.h>  #include?<dlfcn.h>  #include?<mysql>  int?main()  {  ????int?????ret?=?0;  ????int?????i?=?0;  ????MYSQL???mysql;  ????MYSQL???*con?=?NULL;  ????unsigned?int?fieldnum;??  ????printf("hello....n");  ????con?=?mysql_init(&amp;mysql);  ????if?(con?==?NULL)  ????{  ????????ret?=?mysql_errno(&amp;mysql);  ????????printf("func?mysql_init()?err?:%dn",?ret);  ????????return?ret;  ????}  ????con?=?mysql_real_connect(&amp;mysql,?"localhost",?"root",?"123456",?"mydb2",?0,?NULL,?0?);  ????if?(con?==?NULL)  ????{  ????????ret?=?mysql_errno(&amp;mysql);  ????????printf("func?mysql_real_connect()?err?:%dn",?ret);  ????????return?ret;  ????}  ????else  ????{  ????????printf("func?mysql_real_connect()?okn");  ????}  ????//執行sql查詢  ????mysql_query(&amp;mysql,?"set?names?utf8");//解決中文亂碼  ????char?*sql?=?"select?*from?employee";  ????ret?=?mysql_query(&amp;mysql,?sql);  ????if?(ret?!=?0)  ????{  ????????ret?=?mysql_errno(&amp;mysql);  ????????printf("func?mysql_query()?err?:%dn",?ret);  ????????return?ret;  ????}  ????/*  ????//獲取結果集?一次性獲取  ????MYSQL_RES?*?sqlres?=mysql_store_result(?&amp;mysql);  ????if?(sqlres?==?NULL)  ????{  ????????ret?=?mysql_errno(&amp;mysql);  ????????printf("func?mysql_store_result()?err?:%dn",?ret);  ????????return?ret;  ????}  ????*/  ????//對每一行分別進行檢索  ????MYSQL_RES?*?sqlres?=mysql_store_result(&amp;mysql);  ????if?(sqlres?==?NULL)  ????{  ????????ret?=?mysql_errno(&amp;mysql);  ????????printf("func?mysql_store_result()?err?:%dn",?ret);  ????????return?ret;  ????}  ????//從結果集,獲取表頭信息  ????MYSQL_FIELD?*fields?=?mysql_fetch_fields(sqlres);  ????fieldnum?=?mysql_field_count(&amp;mysql);  ????for?(i=0;?i<fieldnum><p>以上就是MySQL入門之簡單數據查詢的內容,更多相關內容請關注PHP中文網(www.php.cn)!</p></fieldnum></mysql></dlfcn.h></string.h></stdlib.h></stdio.h>
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