mysql 指標 C ,指標,mysql

2021-10-18 10:16:31 字數 1751 閱讀 8250

底下是自己寫的一段小**。假設有62條記錄,在查詢完畢後,還會輸出幾條亂碼,感覺應該是指標方面的問題,但找了半天還是修改失敗,望指教……多謝了……#include#include...

底下是自己寫的一段小**。假設有62條記錄,在查詢完畢後,還會輸出幾條亂碼,感覺應該是指標方面的問題,但找了半天還是修改失敗,望指教……多謝了……

#include

#include

#include "mysql.h"

#include

#pragma comment(lib,"libmysql.lib")

using std::cout;

using std::endl;

using std::string;

mysql mysql;

long long* getfield(char* sql)

mysql_row m_row;

mysql_res *m_res;

long long* p = null;

unsigned long long num = 0;

unsigned long i = 0;

mysql_query(&mysql,sql)

m_res = mysql_store_result(&mysql);

num = mysql_num_rows(m_res);

p = new long long [num];

memset(p, '\0', sizeof(long long) * num);

while(m_row = mysql_fetch_row(m_res))

p[i++] = atoi(m_row[0]);

return p;

int prepare()

char host[32] = "localhost";

char user[32] = "root";

char passwd[32] = "";

char dbname[32] = "test";

char log[512];

//初始化資料庫

if(mysql_init(&mysql) == null)

return 1;

else

printf("init success.\n");

//連線資料庫

if(mysql_real_connect(&mysql,host,user,passwd,dbname,0,null,0) == null)

sprintf(log,"fail to connect to database:%s.",mysql_error(&mysql));

return 1;

else

printf("connect to database:%s.\n",dbname);

return 0;

void main()

prepare();

long long *p = null;

p = getfield("select id from user where id>1");

int i = 0;

while(p[i])

delete p;

p = null;

system("pause");

那個,呃……prepare()那個函式可以不用看,用來初始化資料庫連線的,確認過沒問題,主要是getfield(char* sql)那個函式有問題……希望多幫幫忙哈……多謝多謝……

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