Date and time strings

To write specific date and time values, you must write expressions explicitly. The following expressions are specific cases of function calls with date and time strings.

DATE('2000-06-27')
TIME('10.32.55.123456')
TIMESTAMP('2000-06-27-10.32.55.123456')

The character strings '2000-06-27', '10.32.55.123456', and '2000-06-27-10.32.55.123456' are date and time strings.

Date string

Is a character string that represents a date in the format yyyy-mm-dd where yyyy is the year, mm is the month, and dd is the day.

The DATE function converts a date string to a date. The expression like DATE(date_string) specifies the result of such conversion. For example, the expression DATE('2000-06-27') specifies the date June 27, 2000.

Time string

Is a character string that represents a time in the format hh.mm.ss.uuuuuu, where hh is the hour, mm is the minute, ss is the second, and uuuuuu is the microsecond.

The TIME function converts a time string to a time. The expression like TIME(time_string) specifies the result of such conversion. For example, the expression TIME('10.32.55.123456') specifies the time 10 hours 32 minutes 55.123456 seconds.

Timestamp string

Is a character string that represents a timestamp in the format yyyy-mm-dd-hh.mm.ss.uuuuuu where yyyy, mm, dd, hh, mm, ss, and uuuuuu are as above.

The TIMESTAMP function converts a timestamp string to a timestamp. The expression like TIMESTAMP(timestamp_string) specifies the result of such conversion. For example, the expression TIMESTAMP('2000-06-27-10.32.55.123456') specifies the timestamp 10 hours 32 minutes 55.123456 seconds on June 27, 2000.

In some cases you can use a date and time string instead of a date and time value, and the System Date Engine converts the string for you. For example, if CREATION_DATE specifies a date, you can use CREATION_DATE<'2000-06-25'. The System Data Engine converts the date string to a date value and compares the result with the date that is specified by CREATION_DATE.