CREATE TABLE test_customer (
	Id NUMBER(6,0), 
	Name VARCHAR2(20)
);

INSERT INTO test_Customer (Id, Name) VALUES (100,'SMITH');
INSERT INTO test_Customer (Id, Name) VALUES (101,'JONES');
INSERT INTO test_Customer (Id, Name) VALUES (100,'BROWN');

SELECT * FROM test_customer;

--TRUNCATE TABLE test_customer;
DROP TABLE test_customer;

CREATE TABLE test_customer (
	Id NUMBER(6,0) PRIMARY KEY, 
	Name VARCHAR2(20)
);


DROP TABLE IF EXISTS test_customer;

CREATE TABLE test_customer (
	Id NUMBER(6,0), 
	Name VARCHAR2(20),
	CONSTRAINT test_customer_Id_pk PRIMARY KEY (Id)
);

-- Viewing the Data Dictionary
SELECT table_name, num_rows FROM USER_TABLES WHERE table_name != 'HTMLDB_PLAN_TABLE';

-- Table Creation through Sub Queries
CREATE TABLE cust_marketing AS
	(SELECT Id, Lastname, FirstName, City, Province FROM Customers);

SELECT * FROM cust_marketing;

-- Modify Existing Tables
ALTER TABLE Vendors ADD Ext NUMBER(4,0);

ALTER TABLE VENDORS MODIFY Ext NUMBER(5,0);

ALTER TABLE vendors DROP COLUMN Ext;



SELECT table_name, num_rows FROM user_tables 
WHERE table_name != 'HTMLDB_PLAN_TABLE';