(Oracle DB) - 8. Modifying Table

/* Modifying Table */
CREATE TABLE ex2_10
(
	col1 VARCHAR2(10) NOT NULL,
	col2 VARCHAR2(10) NULL,
	create_date DATE DEFAULT SYSDATE
);

	/* Rename Column Name */
ALTER TABLE ex2_10
	RENAME COLUMN col1 TO col11;

DESC ex2_10@myoracle;

	/* Modify Column Data Type */
ALTER TABLE ex2_10
	MODIFY col2 VARCHAR2(30);

DESC ex2_10@myoracle;

	/* Add New Column */
ALTER TABLE ex2_10
	ADD col3 NUMBER;
	
DESC ex2_10@myoracle;

	/* Drop Column */
ALTER TABLE ex2_10
	DROP COLUMN col3;
	
DESC ex2_10@myoracle;

	/* Add Constraint : Primary Key */
ALTER TABLE ex2_10
	ADD CONSTRAINT pk_ex2_10 PRIMARY KEY (col11);

SELECT
	constraint_name,
	constraint_type,
	table_name,
	search_condition
	FROM user_constraints
WHERE table_name = 'EX2_10'
;

	/* Drop Constraint : Primary Key */
	--	Another constraints can be added and dropped.
ALTER TABLE ex2_10
	DROP CONSTRAINT pk_ex2_10;

SELECT
	constraint_name,
	constraint_type,
	table_name,
	search_condition
	FROM user_constraints
WHERE table_name = 'EX2_10'
;