인생은 아름다워

-- Comment 보기
select * from ALL_COL_COMMENTS 
select * from ALL_TAB_COMMENTS​

--테이블 정보
select * from tabs ;
select* from user_tables;

-- Synonyms
SELECT * FROM ALL_SYNONYMS

-- Object 정보
select * from user_objects;

-- 인덱스
CREATE UNIQUE INDEX idx_tablename ON tablename ( col1, col2);
DROP index idx_tablename

-- 컬럼정보 
SELECT * FROM COLS WHERE TABLE_NAME LIKE '%%';
SELECT * FROM ALL_TAB_COLUMNS WHERE TABLE_NAME LIKE '%%';

-- Table 생성
CREATE TABLE table_name
(
  column1 datatype null/not null,  
  ...
  CONSTRAINT constname PRIMARY KEY (col1,...., coln )
);

--제약조건 ( PK 등등)
ALTER TABLE table_name 
ADD CONSTRAINT constraint_name 
PRIMARY KEY (column1, column2, ... column_n);
 
ALTER TABLE table_name
DROP CONSTRAINT constraint_name;

--인덱스
CREATE (unique) INDEX idxname ON tablename (hiredate)
Drop Indexname