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I have some tables and i am trying to add some constraints so when you delete from one table, it deletes all records that are in other tables that reference it

 

CREATE TABLE Employee (
  ssn             NUMBER (4) PRIMARY KEY,
  salary          NUMBER (5),
  phone		  NUMBER (11)
  );

CREATE TABLE Department (
  dno		  NUMBER (1) PRIMARY KEY,
  dname		  VARCHAR2 (20),
  budget	  NUMBER (6)
  );

CREATE TABLE Child (
  name      	  VARCHAR2 (20) UNIQUE,
  age		  NUMBER (2),
  check(age BETWEEN 0 AND 18)
  );	

CREATE TABLE Children (
  ssn		  NUMBER (4),
  name		  VARCHAR2 (20),
  PRIMARY KEY (ssn, name),
  CONSTRAINT parent FOREIGN KEY(ssn) references Employee(ssn) ON DELETE CASCADE CONSTRAINT parent ON UPDATE CASCADE CONSTRAINT CONSTRAINT parent,
  CONSTRAINT child FOREIGN KEY(name) references Child(name) ON DELETE CASCADE CONSTRAINT child ON UPDATE CASCADE CONSTRAINT child
  );

CREATE TABLE Works (
  ssn		  NUMBER (4),
  dno		  NUMBER (1),
  PRIMARY KEY (ssn, dno),
  CONSTRAINT employee FOREIGN KEY(ssn) references Employee(ssn) ON DELETE CASCADE CONSTRAINT employee ON UPDATE CASCADE CONSTRAINT employee, 
  CONSTRAINT department FOREIGN KEY(dno) references Department(dno) ON DELETE CASCADE CONSTRAINT department ON UPDATE CASCADE CONSTRAINT department
  );

CREATE TABLE Manages (
  ssn		  NUMBER (4),
  dno		  NUMBER (1),
  PRIMARY KEY (ssn, dno),
  CONSTRAINT supervisor FOREIGN KEY(ssn) references Employee(ssn) ON DELETE CASCADE CONSTRAINT supervisor ON UPDATE CASCADE CONSTRAINT supervisor, 
  CONSTRAINT depart FOREIGN KEY(dno) references Department(dno) ON DELETE CASCADE CONSTRAINT depart ON UPDATE CASCADE CONSTRAINT depart
  );

CREATE TABLE NewMember (
  ssn		  NUMBER (4),
  dno 		  NUMBER (1)
  );

 

What am i doing wrong with these constraints?

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