c++ sqlite3 create table and insert example

sqlite3.cpp

// From: https://gist.github.com/lotfio/cfbf857bc96a0487b53ed4877658a97b
// Fork: https://gist.github.com/anytizer/44bdc76947b302f22c5c1b67a83d2627

/**
 * Minor Improvements:
 *  Sqlite => DatabaseManager.
 *  One lined insert statements.
 *  Embedded SQLite3 source code from amalgamation.
 *  Access pointer with "this".
 *  OS/compiler specific full path to the database name.
 *  Text conversion in the database fields.
 *  Tick quoted database fields.
 */

#ifdef _WIN64
#define DATABASE_PATH "/tmp/database.db"
#elif !_WIN64
#define DATABASE_PATH "/tmp/database.db"
#endif

//#include <iostream>

#include "sqlite3.h"

static int callback(void *NotUsed, int argc, char **argv, char **azColName)
{
    return 0;
}

class DatabaseManager
{
public:
    sqlite3* db;

public:

    DatabaseManager(const char* fullpath)
    {
        sqlite3_open(fullpath, &this->db);
    }

    ~DatabaseManager()
    {
        sqlite3_close(this->db);
    }

    int execute(const char* sql,int (*callback)(void *, int, char **, char **), char* err = 0)
    {
        return sqlite3_exec(this->db, sql, callback, 0, &err);
    }
};


int main(void)
{
    DatabaseManager conn = DatabaseManager(DATABASE_PATH);

    const char* q1 = \
        "CREATE TABLE `employees` (" \
        "`id`      TEXT NOT NULL," \
        "`name`    TEXT NOT NULL," \
        "`age`     TEXT NOT NULL," \
        "`address` TEXT NOT NULL," \
        "`salary`  TEXT NOT NULL," \
        "PRIMARY KEY(`id`)" \
        ");" \
    ;

    conn.execute(q1, callback);

    const char* q2 = \
        "INSERT INTO `employees` (`id`, `name`, `age`, `address`, `salary`) VALUES ('001', 'Paul',  '32', 'Calif', '20000.00');" \
        "INSERT INTO `employees` (`id`, `name`, `age`, `address`, `salary`) VALUES ('002', 'Allen', '25', 'Texas', '15000.00');" \
        "INSERT INTO `employees` (`id`, `name`, `age`, `address`, `salary`) VALUES ('003', 'Teddy', '23', 'Norwy', '20000.00');" \
        "INSERT INTO `employees` (`id`, `name`, `age`, `address`, `salary`) VALUES ('004', 'Mark',  '25', 'RichM', '65000.00');" \
        "INSERT INTO `employees` (`id`, `name`, `age`, `address`, `salary`) VALUES ('005', 'Test',  '30', 'Addre', '60000.00');" \
        "INSERT INTO `employees` (`id`, `name`, `age`, `address`, `salary`) VALUES ('006', 'Sixt',  '60', 'Addre', '60000.00');" \
    ;
    
    conn.execute(q2, callback);

    return 0;
}