Update README.md

README.md

@@ -1,2 +1,98 @@
 # Scape---Photo-Sharing-Website
-This is a photo sharing website with the following features:
+
+Description:
+A user can have multiple friends and it is stored in the database as a self-relation to the users. A user can post comments on photos. Each comment must be posted by a user and associated with a single user, however a user can post multiple comments. Each Comment is associated with exactly one photo. A photo can have multiple comments. A photo has total participation in relationship with the users. Photos have a weak entity called tags which contain the names of all the tags associated with that photo. Two photos can have the same tag.  A photo is always contained in an album. An album can have multiple photos. Similarly, A user can have multiple albums but an album must be associated to one or more users. 
+
+Relational Schema:
+
+Users
+user_id	first_name	last_name	gender	email 	password	date_of_birth	hometown
+
+Albums
+album_id	name	date_of_creation	owner(user)_id
+
+Photos
+photo_id	no_of_likes	data	caption	user_id	date	album_id
+
+Comments
+comment_id	comment_date	text	photo_id	owner_id
+
+Friends_with
+friend(user)_id	user_id
+
+Tags
+tag_name	photo_id
+
+
+Likes
+user_id	photo_id
+
+
+
+
+SQL Queries:
+
+CREATE TABLE Users
+( user_id INTEGER NOT NULL AUTO_INCREMENT,
+first_name CHAR(30) NOT NULL,
+last_name CHAR(30),
+email CHAR(30),
+password CHAR(32) NOT NULL,
+date_of_birth DATE,
+hometown CHAR(20),
+gender VARCHAR(10),
+PRIMARY KEY(user_id));
+
+CREATE TABLE Albums
+(album_id INTEGER NOT NULL AUTO_INCREMENT,
+name CHAR(30),
+date_of_creation DATETIME default CURRENT_TIMESTAMP,
+owner_id INTEGER NOT NULL,
+PRIMARY KEY (album_id),
+FOREIGN KEY(owner_id) REFERENCES Users(user_id) ON DELETE CASCADE);
+
+CREATE TABLE Photos
+(photo_id INTEGER NOT NULL AUTO_INCREMENT,
+data LONGBLOB,
+caption VARCHAR(255),
+user_id INTEGER NOT NULL,
+date DATETIME default CURRENT_TIMESTAMP,
+album_id INTEGER NOT NULL,
+PRIMARY KEY (photo_id),
+FOREIGN KEY(user_id) REFERENCES Users(user_id) ON DELETE CASCADE,
+FOREIGN KEY(album_id) REFERENCES Albums(album_id) ON DELETE CASCADE);
+
+CREATE TABLE Comments
+(comment_id INTEGER NOT NULL AUTO_INCREMENT,
+comment_date DATETIME default CURRENT_TIMESTAMP,
+text TEXT,
+photo_id INTEGER NOT NULL,
+owner_id INTEGER NOT NULL,
+PRIMARY KEY(comment_id),
+FOREIGN KEY(owner_id) REFERENCES Users(user_id),
+FOREIGN KEY(photo_id) REFERENCES Photos(photo_id) ON DELETE CASCADE);
+
+Additional Assumptions:
+The name of the site is assumed as Scape! A user can like a photo only once.
+
+
+CREATE TABLE Friends
+(friend_id INTEGER NOT NULL,
+user_id INTEGER NOT NULL,
+PRIMARY KEY(friend_id, user_id),	
+FOREIGN KEY(friend_id) REFERENCES Users(user_id),
+FOREIGN KEY(user_id) REFERENCES Users(user_id)); 
+
+CREATE TABLE Tags
+(tag_name VARCHAR(255),
+photo_id INTEGER NOT NULL,
+PRIMARY KEY(tag_name, photo_id),
+ FOREIGN KEY(photo_id) REFERENCES Photos(photo_id) 
+ON DELETE CASCADE);
+
+CREATE TABLE Likes
+(user_id INTEGER,
+photo_id INTEGER NOT NULL,
+PRIMARY KEY(user_id, photo_id),
+ FOREIGN KEY(user_id) REFERENCES Users(user_id),
+FOREIGN KEY(photo_id) REFERENCES Photos(photo_id) ON DELETE CASCADE);