#include <fstream>
#include <iostream>
#include <vector>
#include "Relation.h"
//still in progress
class DBEngine{
vector<Relation> tables;
int size;
public:
DBEngine();
void createTable(string n);
void createTable(string n, vector<Attribute> a);
void createTable(Relation r);
vector<Relation> getRelations();
//void showTable(Relation r);
Relation getTableFromName(string n);
void saveToFile(vector<string> cmds);
//operations
//void selection();
Relation projection(vector<string> input, Relation r);
//void renaming();
//void setUnion();
//void setDiff();
//void crossProduct();
};