Question

我想在我的数据库中设置一些记录此代码将成功创建数据库和表并且在函数“addel”中它会成功地为数据库设置一条记录，但是当它想要从“addel”返回到main时会出现“Segmentation fault（core dumped）”错误... 任何人都可以帮忙吗？

#include <iostream>
#include <vector>
#include <stdlib.h>
#include <sqlite3.h>
#include <cstdio>

using namespace std;

void addel(sqlite3 * db);
void sqlmake(sqlite3 * db);
static int callback(void *NotUsed, int argc, char **argv, char **azColName);

void addel(sqlite3 * db) {
    string temps;
    int temp,x;
    char *cm;
    char *errm;

        x=sqlite3_open("12.db",&db);// open database because it closed before
    if(x) {
        cerr<<"can not creat database";
        exit(1);
    } else {
        cerr<<"open database successfully"<<endl;
    }

    cout<<"name : " ;
    cin>>temps;
    cout<<"age :" ;
    cin>>temp;

    sprintf(cm,"INSERT INTO pipl(ID,name) VALUES (%d,'%s');",temp,temps.c_str()); //creat sql query command
    x=sqlite3_exec(db,cm,callback,0,&errm);
    cout<< cm << endl;
    if(x!=SQLITE_OK) {
        cerr<<"error write record"<<errm<<endl;
        sqlite3_free(errm);
    } else
        cout<<"record written!" << endl;

    cout<<"done"<<endl;
        sqlite3_close(db);

}

//call back function to use for sqlite3_exec function
static int callback(void *NotUsed, int argc, char **argv, char **azColName) {
   int i;
   for(i=0; i<argc; i++){
      printf("%s = %s\n", azColName[i], argv[i] ? argv[i] : "NULL");
   }
   printf("\n");
   return 0;
}

void sqlmake(sqlite3 * db) {
    int x;
    char *cm;
    char *errm;
    x=sqlite3_open("12.db",&db);
    if(x) {
        cerr<<"can not creat database";
        exit(1);
    } else {
        cerr<<"database created successfully"<<endl;
    }
    cm=(char *)"CREATE TABLE pipl(ID INT NOT NULL,name TEXT NOT NULL);";
    x=sqlite3_exec(db,cm,callback,0,&errm);
    if(x!=SQLITE_OK) {
        cerr<<"error bulding table"<<errm<<endl;
        sqlite3_free(errm);
    } else
        cout<<"table created";

    sqlite3_close(db);
    return ;
}

int main() {
    int x,x1;
    string temps;
    sqlite3 *db;
    sqlmake(db); //make database file and table in it
    addel(db); // add a record to table (problem)

    return 0;
}

Answer 1

你必须预订cm的空间。 sprintf写一个缓冲区

char *cm

只创建一个指针，但不要预留空间。

char cm[100]

预订网站，其中sprintf可以写出100个字符，为期望的空间更改100个。

cql中的sqlite分段错误

1 个答案: