#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
	//Relation selection();
	Relation projection(vector<string> input, Relation r);
	void rename(Relation r, vector<string> oldnames, vector<string> newnames);
	//void setUnion();
	//void setDiff();
	//void crossProduct();
};