C++写sqlite3

我很乐意回答您的问题。下面是一个简单的SQLite3示例程序，它展示了如何在C语言中使用SQLite3库进行数据库操作：

#include <stdio.h>
#include <stdlib.h>
#include <sqlite3.h>

// 回调函数
static int callback(void *data, 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;
}

int main(int argc, char *argv[])
{
    sqlite3 *db;
    char *zErrMsg = 0;
    int rc;
    const char *sql;

    // 打开数据库
    rc = sqlite3_open("test.db", &db);
    if(rc)
    {
        fprintf(stderr, "Can't open database: %s\n", sqlite3_errmsg(db));
        sqlite3_close(db);
        exit(1);
    }

    // 创建表
    sql = "CREATE TABLE COMPANY("
          "ID INT PRIMARY KEY     NOT NULL,"
          "NAME           TEXT    NOT NULL,"
          "AGE            INT     NOT NULL,"
          "ADDRESS        CHAR(50),"
          "SALARY         REAL);";

    rc = sqlite3_exec(db, sql, callback, 0, &zErrMsg);

    if(rc != SQLITE_OK)
    {
        fprintf(stderr, "SQL error: %s\n", zErrMsg);
        sqlite3_free(zErrMsg);
    }
    else
    {
        fprintf(stdout, "Table created successfully\n");
    }

    // 插入数据
    sql = "INSERT INTO COMPANY (ID,NAME,AGE,ADDRESS,SALARY) "
          "VALUES (1, 'Paul', 32, 'California', 20000.00 ); "
          "INSERT INTO COMPANY (ID,NAME,AGE,ADDRESS,SALARY) "
          "VALUES (2, 'Allen', 25, 'Texas', 15000.00 ); "
          "INSERT INTO COMPANY (ID,NAME,AGE,ADDRESS,SALARY)"
          "VALUES (3, 'Teddy', 23, 'Norway', 20000.00 );"
          "INSERT INTO COMPANY (ID,NAME,AGE,ADDRESS,SALARY)"
          "VALUES (4, 'Mark', 25, 'Rich-Mond', 65000.00 );";

    rc = sqlite3_exec(db, sql, callback, 0, &zErrMsg);

    if(rc != SQLITE_OK)
    {
        fprintf(stderr, "SQL error: %s\n", zErrMsg);
        sqlite3_free(zErrMsg);
    }
    else
    {
        fprintf(stdout, "Records created successfully\n");
    }

    // 查询数据
    sql = "SELECT * from COMPANY";

    rc = sqlite3_exec(db, sql, callback, 0, &zErrMsg);

    if(rc != SQLITE_OK)
    {
        fprintf(stderr, "SQL error: %s\n", zErrMsg);
        sqlite3_free(zErrMsg);
    }
    else
    {
        fprintf(stdout, "Operation done successfully\n");
    }

    // 关闭数据库
    sqlite3_close(db);

    return 0;
}

以上示例程序将创建名为"test.db"的SQLite3数据库，并在其中创建一个名为"COMPANY"的表。然后，它会向表中插入一些数据，并查询该表以显示结果。为了运行此程序，您将需要安装SQLite3库并编译上述代码。