text: 
  CREATE TABLE TB_STOCK (
    ID_STOCK      BIGSERIAL NOT NULL,
    COD_STOCK     varchar(6) NOT NULL,
    NU_DIVIDEND_YIELD  NUMERIC ,
    NU_MARKET_VALUE_BILLION  NUMERIC,
    NU_COMPANY_VALUE_BILLION  NUMERIC,
    NU_STAR  NUMERIC,
    CONSTRAINT PK_STOCK
      PRIMARY KEY (ID_STOCK)
  );
  
  ALTER TABLE TB_STOCK
   ADD  CONSTRAINT UK_COD_STOCK UNIQUE (COD_STOCK);
  
  COMMENT ON TABLE TB_STOCK
    IS 'Table with info for stocks';
  
  COMMENT ON COLUMN TB_STOCK.NU_STAR
    IS 'Ranges from 1 to 10 with 10 being excellent';
  