CREATE TABLE "user_account" (	id serial not null,	login character varying(50) not null,	password character varying(50) not null,	email character varying(250) not null,	PRIMARY KEY (id));CREATE TABLE "feed" (	id serial not null,	url character varying(250) not null,	feedUrl character varying(250) not null,	title character varying(1000) not null,	description character varying(2000) not null,	lastUpdate timestamp not null,	PRIMARY KEY (id));CREATE TABLE "entry" (	id serial not null,	id_feed integer references feed(id),	url character varying(250) not null,	title character varying(1000) not null,	description character varying(2000) not null,	"date" timestamp not null,	PRIMARY KEY (id));CREATE TABLE "entry_read_by_user" (	id serial not null,	id_entry integer references entry(id),	id_user integer references user_account(id));CREATE TABLE "user_feed" (	id serial not null,	id_user integer references user_account(id),	id_feed integer references feed(id),	PRIMARY KEY (id));