diff --git a/PHelpers.cpp b/PHelpers.cpp
new file mode 100755
index 0000000..ad215fc
--- /dev/null
+++ b/PHelpers.cpp
@@ -0,0 +1,120 @@
+#include <iostream>
+#include <sstream>
+#include <string>
+#include <vector>
+#include "PHelpers.h"
+
+using namespace std;
+
+PAttribute::PAttribute(){
+	name = "~";
+	type = "~";
+	key = false;
+	size = 0;
+}
+
+PAttribute::PAttribute(string str, string t){
+	name = str;
+	type = t;
+	key = false;
+	size = 0;
+}
+
+PAttribute::PAttribute(string str, string t, int s){
+	name = str;
+	type = t;
+	key = false;
+	size = s;
+}
+
+PUnion::PUnion(){
+	Un1 = "~";
+	Un2 = "~";
+}
+
+PUnion::PUnion(string s1, string s2){
+	Un1 = s1;
+	Un2 = s2;
+}
+
+string PUnion::getPUnion(){ 
+	return "Union of " + Un1 + " and " + Un2; 
+}
+
+PProduct::PProduct(){
+	Pr1 = "~";
+	Pr2 = "~";
+}
+
+PProduct::PProduct(string s1, string s2){
+	Pr1 = s1;
+	Pr2 = s2;
+}
+
+string PProduct::getPProduct(){ 
+	return "Product of " + Pr1 + " and " + Pr2; 
+}
+
+PDifference::PDifference(){
+	D1 = "~";
+	D2 = "~";
+}
+
+PDifference::PDifference(string s1, string s2){
+	D1 = s1;
+	D2 = s2;
+}
+
+string PDifference::getPDifference(){
+	return "Difference of " + D1 + " and " + D2;
+}
+
+PRenaming::PRenaming(){
+	newName = "~";
+	oldName = "~";
+}
+
+PRenaming::PRenaming(string s1, string s2){
+	newName = s1;
+	oldName = s2;
+}
+
+string PRenaming::doRename(){
+	return "Renaming " + oldName + " to " + newName;
+}
+
+PProjection::PProjection(){
+	newName = "~";
+	oldName = "~";
+}
+
+PProjection::PProjection(string s1, string s2){
+	newName = s1;
+	oldName = s2;
+}
+
+string PProjection::doPProjection(){
+	return "Projecting " + oldName + " onto " + newName;
+}
+
+PComparison::PComparison(){
+	op.setPOp("~");
+	operand1.setPOperand("~");
+	operand2.setPOperand("~");
+}
+
+PComparison::PComparison(string str1, string str2, string str3){
+	operand1.setPOperand(str1);
+	op.setPOp(str2);
+	operand2.setPOperand(str3);
+}
+
+void PComparison::setPComparison(string str1, string str2, string str3){
+	operand1.setPOperand(str1);
+	op.setPOp(str2);
+	operand2.setPOperand(str3);
+}
+
+string PComparison::getPComparison(){
+	return operand1.getPOperand() + " " + op.getPOp() + " " + operand2.getPOperand();
+}
\ No newline at end of file
diff --git a/PHelpers.h b/PHelpers.h
new file mode 100755
index 0000000..a86f47b
--- /dev/null
+++ b/PHelpers.h
@@ -0,0 +1,165 @@
+#include <iostream>
+#include <sstream>
+#include <string>
+#include <vector>
+#include "DBEngine.h"
+
+using namespace std;
+
+class PRelation{
+	string name;
+	
+	public: 
+		PRelation(){ name = "~"; }
+		PRelation(string str){ name = str; }
+		void setPRelation(string str){ name = str; }	
+		string getName(){ return name; }
+};
+
+class PAttribute{
+	string name;
+	string type;
+	bool key;
+	int size;
+	
+	public:
+		PAttribute();
+		PAttribute(string str, string t);
+		PAttribute(string str, string t, int s);
+		void setPAttributeName(string str){ name = str; }
+		void setPAttributeType(string t){ type = t; }
+		void setPAttributeKey(){ key = true; }
+		void setPAttributeSize(int s){ size = s; }
+		string getPAttribute(){ return name; }
+		string getPAttributeType(){ return type; }
+		bool getPAttributeKey(){ return key; }
+		int getPAttributeSize(){ return size; }
+};
+
+class PUnion{
+	string Un1;
+	string Un2;
+	
+	public:
+		PUnion();
+		PUnion(string s1, string s2);
+		string getPUnion();
+};
+
+class PProduct{
+	string Pr1;
+	string Pr2;
+	
+	public:
+		PProduct();
+		PProduct(string s1, string s2);
+		string getPProduct();
+};
+
+class PDifference{
+	string D1;
+	string D2;
+	
+	public:
+		PDifference();
+		PDifference(string s1, string s2);
+		string getPDifference();
+};
+
+class PRenaming{
+	string newName;
+	string oldName;
+	
+	public:
+		PRenaming();
+		PRenaming(string s1, string s2);
+		string doRename();
+};
+
+class PProjection{
+	string newName;
+	string oldName;
+	
+	public:
+		PProjection();
+		PProjection(string s1, string s2);
+		string doPProjection();
+};
+
+class POperand{
+	string op;
+	
+	public:
+		POperand(){ op = "~"; }
+		POperand(string str){ op = str; }
+		void setPOperand(string str){ op = str; }
+		string getPOperand(){ return op; }
+};
+
+class POp{
+	string op;
+	
+	public: 
+		POp(){ op = "~"; }
+		POp(string str){ op = str; }
+		void setPOp(string str){ op = str; }
+		string getPOp(){ return op; }
+};
+
+class PComparison{
+	POp op;
+	POperand operand1;
+	POperand operand2;
+	
+	public:
+		PComparison();
+		PComparison(string str1, string str2, string str3);
+		void setPComparison(string str1, string str2, string str3);
+		string getPComparison();
+};
+
+class PConjunction{
+	string conj;
+	
+	public:
+		PConjunction(){ conj = "~"; }
+		PConjunction(string str){ conj = str; }
+		void setPConjunction(string str){ conj = str; }
+		string getPConjunction(){ return conj; }
+};
+
+class PCondition{
+	string cond;
+	
+	public:
+		PCondition(){ cond = "~"; }
+		PCondition(string str){ cond = str; }
+		void setPCondition(string str){ cond = str; }
+		string getPCondition(){ return cond; }
+};
+
+class PSelection{
+	string select;
+	
+	public:
+		PSelection(){ select = "~"; }
+		PSelection(string str){ select = str; }
+		string getPSelection(){ return select; }
+};
+
+class PExpression{
+	PRelation rel;
+	PSelection sel;
+	PProjection proj;
+	PRenaming ren;
+	PUnion un;
+	PDifference diff;
+	PProduct prod;
+	string temp;
+	
+	public:
+		PExpression();
+		PExpression(string str){ temp = str; }
+		void setPExpression(string str){ temp = str; }
+		string getPExpression(){ return temp; }
+};
\ No newline at end of file
diff --git a/Parser.cpp b/Parser.cpp
index 86ac480..4b7035e 100755
--- a/Parser.cpp
+++ b/Parser.cpp
@@ -1,16 +1,15 @@
-#include <string>       // std::string
-#include <iostream>     // std::cout
-#include <fstream>		// std::ofstream
-#include <sstream>      // std::stringstream
-#include <vector>
+#include <fstream>
+#include <iostream>
+#include <sstream>
 #include <string>
-#include "Parser.h"
 #include <tuple>
+#include <vector>
+#include "Parser.h"
+#include "PHelpers.h"
 
 using namespace std;
 
-vector<string> tokenize(string ss)
-{
+vector<string> tokenize(string ss){
 	string tempString;
 	stringstream lineStream(ss);
 	vector<string> output;
@@ -22,8 +21,7 @@ vector<string> tokenize(string ss)
 	return output;
 }
 
-void displayTokenList(vector<string> input)
-{
+void displayTokenList(vector<string> input){
 	cout<<"TokenList: "<<endl;
 	for (int i = 0; i < input.size(); ++i)
 	{
@@ -31,8 +29,7 @@ void displayTokenList(vector<string> input)
 	}
 }
 
-Relation condition(vector<string> input, Relation &r, DBEngine &engine)
-{
+Relation condition(vector<string> input, Relation &r, DBEngine &engine){
 	Relation rfinal = r;
 
 	Attribute a1 = r.getAttributeByName(input[0]);
@@ -41,19 +38,16 @@ Relation condition(vector<string> input, Relation &r, DBEngine &engine)
 	input.erase(input.begin());
 	Attribute a2;
 	string c;
-	if(r.isAttribute(input[0]))
-	{
+	if(r.isAttribute(input[0])){
 		a2 = r.getAttributeByName(input[0]);
 		input.erase(input.begin());
-		for(int i = 0; i < r.getAttributes().size(); ++i)
-		{
-			if(r.getAttributes()[i].getName() == a1.getName())
-			{
+		
+		for(int i = 0; i < r.getAttributes().size(); ++i){
+			if(r.getAttributes()[i].getName() == a1.getName()){
 				int offset = 0;
-				if(op == "==")
-				{
-					for(int x = 0; x < r.getAttributeByName(a1.getName()).getSize(); ++x)
-					{
+				
+				if(op == "=="){
+					for(int x = 0; x < r.getAttributeByName(a1.getName()).getSize(); ++x){
 						if(r.getAttributeByName(a1.getName()).getValues()[x] != r.getAttributeByName(a2.getName()).getValues()[x])
 						{
 							rfinal.removeTuple(x - offset);
@@ -61,90 +55,76 @@ Relation condition(vector<string> input, Relation &r, DBEngine &engine)
 						}
 					}
 				}
-				else if(op == "!=")
-				{
-					for(int x = 0; x < r.getAttributeByName(a1.getName()).getSize(); ++x)
-					{
-						if(r.getAttributeByName(a1.getName()).getValues()[x] == r.getAttributeByName(a2.getName()).getValues()[x])
-						{
+				
+				else if(op == "!="){
+					for(int x = 0; x < r.getAttributeByName(a1.getName()).getSize(); ++x){
+						if(r.getAttributeByName(a1.getName()).getValues()[x] == r.getAttributeByName(a2.getName()).getValues()[x]){
 							rfinal.removeTuple(x - offset);
 							offset += 1;
 						}
 					}
 				}
-				else if(op == ">=")
-				{
-					if(r.getAttributeByName(a1.getName()).getType() == "INTEGER" && r.getAttributeByName(a2.getName()).getType() == "INTEGER")
-					{
-						for(int x = 0; x < r.getAttributeByName(a1.getName()).getSize(); ++x)
-						{
-							if(stoi(r.getAttributeByName(a1.getName()).getValues()[x]) < stoi(r.getAttributeByName(a2.getName()).getValues()[x]))
-							{
+				
+				else if(op == ">="){
+					if(r.getAttributeByName(a1.getName()).getType() == "INTEGER" && r.getAttributeByName(a2.getName()).getType() == "INTEGER"){
+						for(int x = 0; x < r.getAttributeByName(a1.getName()).getSize(); ++x){
+							if(stoi(r.getAttributeByName(a1.getName()).getValues()[x]) < stoi(r.getAttributeByName(a2.getName()).getValues()[x])){
 								rfinal.removeTuple(x - offset);
 								offset += 1;
 							}
 						}
 					}
-					else
-					{
-						cout << "Attribute type is not an INTEGER." << endl;
-						exit(1);
-					}
-				}
-				else if(op == "<=")
-				{
-					if(r.getAttributeByName(a1.getName()).getType() == "INTEGER" && r.getAttributeByName(a2.getName()).getType() == "INTEGER")
-					{
-						for(int x = 0; x < r.getAttributeByName(a1.getName()).getSize(); ++x)
-						{
-							if(stoi(r.getAttributeByName(a1.getName()).getValues()[x]) > stoi(r.getAttributeByName(a2.getName()).getValues()[x]))
-							{
-								rfinal.removeTuple(x - offset);
-								offset += 1;
-							}
-						}
-					}
-					else
-					{
-						cout << "Attribute type is not an INTEGER." << endl;
-						exit(1);
-					}
-				}
-				else if(op == ">")
-				{
 					
-					if(r.getAttributeByName(a1.getName()).getType() == "INTEGER" && r.getAttributeByName(a2.getName()).getType() == "INTEGER")
-					{
-						for(int x = 0; x < r.getAttributeByName(a1.getName()).getSize(); ++x)
-						{
-							if(stoi(r.getAttributeByName(a1.getName()).getValues()[x]) <= stoi(r.getAttributeByName(a2.getName()).getValues()[x]))
-							{
-								rfinal.removeTuple(x - offset);
-								offset += 1;
-							}
-						}
-					}
-					else
-					{
+					else{
 						cout << "Attribute type is not an INTEGER." << endl;
 						exit(1);
 					}
 				}
-				else if(op == "<")
-				{
-					if(r.getAttributeByName(a1.getName()).getType() == "INTEGER" && r.getAttributeByName(a2.getName()).getType() == "INTEGER")
-					{
-						for(int x = 0; x < r.getAttributeByName(a1.getName()).getSize(); ++x)
-						{
-							if(stoi(r.getAttributeByName(a1.getName()).getValues()[x]) >= stoi(r.getAttributeByName(a2.getName()).getValues()[x]))
-							{
+				
+				else if(op == "<="){
+					if(r.getAttributeByName(a1.getName()).getType() == "INTEGER" && r.getAttributeByName(a2.getName()).getType() == "INTEGER"){
+						for(int x = 0; x < r.getAttributeByName(a1.getName()).getSize(); ++x){
+							if(stoi(r.getAttributeByName(a1.getName()).getValues()[x]) > stoi(r.getAttributeByName(a2.getName()).getValues()[x])){
 								rfinal.removeTuple(x - offset);
 								offset += 1;
 							}
 						}
 					}
-					else
-					{
+					
+					else{
+						cout << "Attribute type is not an INTEGER." << endl;
+						exit(1);
+					}
+				}
+				
+				else if(op == ">"){
+					
+					if(r.getAttributeByName(a1.getName()).getType() == "INTEGER" && r.getAttributeByName(a2.getName()).getType() == "INTEGER"){
+						for(int x = 0; x < r.getAttributeByName(a1.getName()).getSize(); ++x){
+							if(stoi(r.getAttributeByName(a1.getName()).getValues()[x]) <= stoi(r.getAttributeByName(a2.getName()).getValues()[x])){
+								rfinal.removeTuple(x - offset);
+								offset += 1;
+							}
+						}
+					}
+					
+					else{
+						cout << "Attribute type is not an INTEGER." << endl;
+						exit(1);
+					}
+				}
+				
+				else if(op == "<"){
+					if(r.getAttributeByName(a1.getName()).getType() == "INTEGER" && r.getAttributeByName(a2.getName()).getType() == "INTEGER"){
+						for(int x = 0; x < r.getAttributeByName(a1.getName()).getSize(); ++x){
+							if(stoi(r.getAttributeByName(a1.getName()).getValues()[x]) >= stoi(r.getAttributeByName(a2.getName()).getValues()[x])){
+								rfinal.removeTuple(x - offset);
+								offset += 1;
+							}
+						}
+					}
+					
+					else{
 						cout << "Attribute type is not an INTEGER." << endl;
 						exit(1);
 					}
@@ -152,22 +132,17 @@ Relation condition(vector<string> input, Relation &r, DBEngine &engine)
 			}
 		}
 	}
-	else if(input[0].at(0) == '\"')
-	{
+	
+	else if(input[0].at(0) == '\"'){
 		c = input[0].substr(1, input[0].find_last_of("\"") - 1);
 		input.erase(input.begin());
 		int offset = 0;
 		//input.erase(input.begin());
-		if(op == "==")
-		{
-			for(int i = 0; i < r.getAttributes().size(); ++i)
-			{
-				if(r.getAttributes()[i].getName() == a1.getName())
-				{
-					for(int j = 0; j < r.getAttributeByName(a1.getName()).getValues().size(); ++j)
-					{
-						if(r.getAttributeByName(a1.getName()).getValues()[j] != c)
-						{
+		if(op == "=="){
+			for(int i = 0; i < r.getAttributes().size(); ++i){
+				if(r.getAttributes()[i].getName() == a1.getName()){
+					for(int j = 0; j < r.getAttributeByName(a1.getName()).getValues().size(); ++j){
+						if(r.getAttributeByName(a1.getName()).getValues()[j] != c){
 							rfinal.removeTuple(j - offset);
 							offset += 1;
 						}
@@ -175,6 +150,9 @@ Relation condition(vector<string> input, Relation &r, DBEngine &engine)
 				}
 			}
 		}
+		
+		//continue stylistic homogenization here
+		
 		else if(op == "!=")
 		{
 			for(int i = 0; i < r.getAttributes().size(); ++i)
@@ -192,6 +170,7 @@ Relation condition(vector<string> input, Relation &r, DBEngine &engine)
 				}
 			}
 		}
+		
 		else if(op == ">=")
 		{
 			if(r.getAttributeByName(a1.getName()).getType() == "INTEGER")
@@ -733,10 +712,9 @@ vector<string> createCMD(vector<string> input, DBEngine &engine)
 			return input;
 		}
 			
-		else cout<<"Syntax error! 2"<<endl;
+		else cout<<"Syntax error! 2"<<endl; //refine
 	}
-	else cout<<"Syntax error! 1"<<endl;
-	
+	else cout<<"Syntax error! 1"<<endl; //refine
 }
 
 vector<string> insertCMD(vector<string> input, DBEngine &engine)
diff --git a/Parser.h b/Parser.h
index 8418339..94611a0 100755
--- a/Parser.h
+++ b/Parser.h
@@ -1,267 +1,23 @@
-#include <string>       // std::string
-#include <iostream>     // std::cout
-#include <sstream>      // std::stringstream
-#include <vector>
-#include <string>
-#include "DBEngine.h"
-
-using namespace std;
-
-class PRelation
-{
-	string name;
-	
-	public: 
-		PRelation() { name = "~"; }
-		PRelation(string str) { name = str; }
-		void setPRelation(string str) { name = str; }	
-		string getName() { return name; }
-};
-
-class PAttribute
-{
-	string name;
-	string type;
-	bool key;
-	int size;
-	
-	public:
-		PAttribute() {
-			name = "~";
-			type = "~";
-			key = false;
-			size = 0;
-		}
-		
-		PAttribute(string str, string t) {
-			name = str;
-			type = t;
-			key = false;
-			size = 0;
-		}
-		
-		PAttribute(string str, string t, int s) {
-			name = str;
-			type = t;
-			key = false;
-			size = s;
-		}
-		
-		void setPAttributeName(string str) { name = str; }
-		void setPAttributeType(string t) { type = t; }
-		void setPAttributeKey() { key = true; }
-		void setPAttributeSize(int s) { size = s; }
-		string getPAttribute() { return name; }
-		string getPAttributeType() { return type; }
-		bool getPAttributeKey() { return key; }
-		int getPAttributeSize() { return size; }
-};
-
-class PUnion
-{
-	string Un1;
-	string Un2;
-	
-	public:
-		PUnion() {
-			Un1 = "~";
-			Un2 = "~";
-		}
-		
-		PUnion(string s1, string s2) {
-			Un1 = s1;
-			Un2 = s2;
-		}
-		
-		string getPUnion() {
-			return "Union of " + Un1 + " and " + Un2;
-		}
-};
-
-class PProduct
-{
-	string Pr1;
-	string Pr2;
-	
-	public:
-		PProduct() {
-			Pr1 = "~";
-			Pr2 = "~";
-		}
-		
-		PProduct(string s1, string s2) {
-			Pr1 = s1;
-			Pr2 = s2;
-		}
-		
-		string getPProduct() {
-			return "Product of " + Pr1 + " and " + Pr2;
-		}
-};
-
-class PDifference
-{
-	string D1;
-	string D2;
-	
-	public:
-		PDifference() {
-			D1 = "~";
-			D2 = "~";
-		}
-		
-		PDifference(string s1, string s2) {
-			D1 = s1;
-			D2 = s2;
-		}
-		
-		string getPDifference() {
-			return "Difference of " + D1 + " and " + D2;
-		}
-};
-
-class PRenaming
-{
-	string newName;
-	string oldName;
-	
-	public:
-		PRenaming() {
-			newName = "~";
-			oldName = "~";
-		}
-		
-		PRenaming(string s1, string s2) {
-			newName = s1;
-			oldName = s2;
-		}
-		
-		string doRename() {
-			return "Renaming " + oldName + " to " + newName;
-		}
-};
-
-class PProjection
-{
-	string newName;
-	string oldName;
-	
-	public:
-		PProjection() {
-			newName = "~";
-			oldName = "~";
-		}
-		
-		PProjection(string s1, string s2) {
-			newName = s1;
-			oldName = s2;
-		}
-		
-		string doPProjection() {
-			return "Projecting " + oldName + " onto " + newName;
-		}
-};
-
-class POperand
-{
-	string op;
-	
-	public:
-		POperand() { op = "~"; }
-		POperand(string str) { op = str; }
-		void setPOperand(string str) { op = str; }
-		string getPOperand() { return op; }
-};
-
-class POp
-{
-	string op;
-	
-	public: 
-		POp() { op = "~"; }
-		POp(string str) { op = str; }
-		void setPOp(string str) { op = str; }
-		string getPOp() { return op; }
-};
-
-class PComparison
-{
-	POp op;
-	POperand operand1;
-	POperand operand2;
-	
-	public:
-		PComparison() {
-			op.setPOp("~");
-			operand1.setPOperand("~");
-			operand2.setPOperand("~");
-		}
-		
-		PComparison(string str1, string str2, string str3) {
-			operand1.setPOperand(str1);
-			op.setPOp(str2);
-			operand2.setPOperand(str3);
-		}
-		
-		void setPComparison(string str1, string str2, string str3) {
-			operand1.setPOperand(str1);
-			op.setPOp(str2);
-			operand2.setPOperand(str3);
-		}
-		
-		string getPComparison() {
-			return operand1.getPOperand() + " " + op.getPOp() + " " + operand2.getPOperand();
-		}
-};
-
-class PConjunction
-{
-	string conj;
-	public:
-		PConjunction() { conj = "~"; }
-		PConjunction(string str) { conj = str; }
-		void setPConjunction(string str) { conj = str; }
-		string getPConjunction() { return conj; }
-};
-
-class PCondition
-{
-	string cond;
-	public:
-	
-		PCondition() { cond = "~"; }
-		PCondition(string str) { cond = str; }
-		void setPCondition(string str) { cond = str; }
-		string getPCondition() { return cond; }
-};
-
-class PSelection
-{
-	string select;
-	public:
-		PSelection() { select = "~"; }
-		PSelection(string str) { select = str; }
-		string getPSelection() { return select; }
-};
-
-class PExpression
-{
-	PRelation rel;
-	PSelection sel;
-	PProjection proj;
-	PRenaming ren;
-	PUnion un;
-	PDifference diff;
-	PProduct prod;
-	string temp;
-	
-	public:
-	
-		PExpression();
-		PExpression(string str) { temp = str; }
-		void setPExpression(string str) { temp = str; }
-		string getPExpression() { return temp; }
-};
-
-void parse(string s, DBEngine &e);
-void parseList(vector<string> input, DBEngine &engine);
\ No newline at end of file
+#include <iostream>
+#include <sstream>
+#include <string>
+#include <vector>
+#include "DBEngine.h"
+
+std::vector<std::string> tokenize(std::string ss);
+void displayTokenList(std::vector<std::string> input);
+Relation condition(std::vector<std::string> input, Relation &r, DBEngine &engine);
+tuple<std::vector<std::string>, Relation> expression(std::vector<std::string> input, DBEngine &engine);
+std::vector<std::string> showCMD(std::vector<std::string> input, DBEngine &engine);
+std::vector<std::string> saveCMD(std::vector<std::string> input, DBEngine &engine);
+std::vector<std::string> closeCMD(std::vector<std::string> input, DBEngine &engine);
+std::vector<std::string> openCMD(std::vector<std::string> input, DBEngine &engine);
+std::vector<std::string> exitCMD(std::vector<std::string> input, DBEngine &engine);
+std::vector<std::string> createCMD(std::vector<std::string> input, DBEngine &engine);
+std::vector<std::string> insertCMD(std::vector<std::string> input, DBEngine &engine);
+std::vector<std::string> updateCMD(std::vector<std::string> input, DBEngine &engine);
+std::vector<std::string> deleteCMD(std::vector<std::string> input, DBEngine &engine);
+std::vector<std::string> query(std::vector<std::string> input, DBEngine &engine);
+void par_line(std::vector<std::string> input, DBEngine &engine);
+void parse(std::string s, DBEngine &e);
+void parseList(std::vector<std::string> input, DBEngine &engine);
\ No newline at end of file
diff --git a/a.out b/a.out
index 4753e8d..b210e4a 100755
Binary files a/a.out and b/a.out differ