CREATE TABLE "Conversations" (
	"Id" int,
	"Subject" varchar(255),
	"CreatedOn" datetime,
	"IsSeen" bool,
	"Sender_Id" int FOREIGN KEY("Sender_Id") REFERENCES "Users" ("Id"),
	"Receiver_Id" int FOREIGN KEY("Receiver_Id") REFERENCES "Users" ("Id")
);
CREATE TABLE "Messages" (
	"Id" int PRIMARY KEY,
	"Body" varchar(255),
	"UserAgent" varchar(255),
	"IsRead" bool,
	"SentOn" datetime,
	"Conversation_Id" int FOREIGN KEY("Conversation_Id") REFERENCES "Conversations" ("Id"),
	"Sender_Id" int FOREIGN KEY("Sender_Id") REFERENCES "Users" ("Id"),
	"Parent_Id" int FOREIGN KEY("Parent_Id") REFERENCES "Messages" ("Id")
);
CREATE TABLE "Users" (
	"Id" int PRIMARY KEY,
	"UserName" varchar(255),
	"DisplayName" varchar(255),
	"HashPassword" varchar(255),
	"Email" varchar(255),
	"..." varchar(255)
);
CREATE TABLE "Attachments" (
	"Id" int PRIMARY KEY,
	"FileName" varchar(255),
	"ContentType" varchar(255),
	"Extension" varchar(255),
	"Size" int,
	"AttachedOn" datetime,
	"Conversation_Id" int FOREIGN KEY("Conversation_Id") REFERENCES "Conversations" ("Id"),
	"Attacher_Id" int FOREIGN KEY("Attacher_Id") REFERENCES "Users" ("Id")
);