Oracle9i 常量

大类 模型
TEXT [N]'chars'
INTEGER [ + | - ] digits
NUMBER 
[ + | - ]
{ digits[.][digits] | .digits }
[{ E | e } [ + | - ] digits ]
interval_year_to_month 
INTERVAL 'integer [- integer]' 
{ YEAR | MONTH } [( precision )] [TO { YEAR | MONTH }]
interval_day_to_second 
INTERVAL ' { integer | integer time_expr | time_expr } ' 
{ { DAY | HOUR | MINUTE } [( leading_precision )]) 
| SECOND [( leading_precision [, fractional_seconds_precision] )]
} 
[TO { DAY | HOUR | MINUTE | SECOND [( fractional_seconds_precision )] }]
Form of Interval Literal Interpretation

INTERVAL '4 5:12:10.222' DAY TO SECOND(3)

4 days, 5 hours, 12 minutes, 10 seconds, and 222 thousandths of a second.

INTERVAL '4 5:12' DAY TO MINUTE

4 days, 5 hours and 12 minutes.

INTERVAL '400 5' DAY(3) TO HOUR

400 days 5 hours.

INTERVAL '400' DAY(3)

400 days.

INTERVAL '11:12:10.2222222' HOUR TO SECOND(7)

11 hours, 12 minutes, and 10.2222222 seconds.

INTERVAL '11:20' HOUR TO MINUTE

11 hours and 20 minutes.

INTERVAL '10' HOUR

10 hours.

INTERVAL '10:22' MINUTE TO SECOND

10 minutes 22 seconds.

INTERVAL '10' MINUTE

10 minutes.

INTERVAL '4' DAY

4 days.

INTERVAL '25' HOUR

25 hours.

INTERVAL '40' MINUTE

40 minutes.

INTERVAL '120' HOUR(3)

120 hours

INTERVAL '30.12345' SECOND(2,4)

30.1235 seconds. The fractional second '12345' is rounded to '1235' because the precision is 4