This constant combines CURRENT DATE and CURRENT TIME to form a TIMESTAMP value, which contains the year, month, day, hour,
minute, second, and fraction of a second. The precision of the fraction is set to 3 decimal places. The accuracy of this constant
is limited by the accuracy of the system clock. See "CURRENT TIMESTAMP special value" under "Special values in UltraLite"
in the SQL Anywhere documentation set.
The default value of existing tables can be determined by querying the system table TableSchema.SYS_COLUMNS's column_default