dataType.md

• https://www.techonthenet.com/oracle/datatypes.php
• lob can not be primary key, can not in distinct, group by, order by
• interval year: nếu khác default (2 chữ số) thì cần chỉ định, ví dụ '100' year(3)
  • https://www.oracletutorial.com/oracle-basics/oracle-interval/
• Oracle supports two INTERVAL data types:
  • INTERVAL YEAR TO MONTH – used to represent a span of years and months
  • INTERVAL DAY TO SECOND – used to represent a span of days, hours, minutes, seconds, and fractional seconds
  • Correct Statements:
    • INTERVAL DAY TO SECOND columns support fractions of seconds.
      • True – The SECOND part can have fractional precision, like INTERVAL DAY TO SECOND(3) allowing milliseconds.
    • INTERVAL YEAR TO MONTH columns support yearly intervals. (tính trên đơn vị năm)
      • True – These columns can store intervals that include years, such as INTERVAL '2-0' YEAR TO MONTH.
    • INTERVAL YEAR TO MONTH columns support monthly intervals within a range of years. (tính trên đơn vị tháng)
      • True – For example, INTERVAL '1-6' YEAR TO MONTH represents 1 year and 6 months.
  • INTERVAL '350' MONTH
    • This represents a period of 350 months.
    • Oracle formats INTERVAL MONTH as: +YY-MM
    • 350 months = 29 years and 2 months
    • So Oracle displays this as: +29-02