Oracle functions are built into Oracle and are available for use in various appropriate Oracle statements. You can also create your own function using PL/SQL.
| Function | Description |
|---|---|
| ADD_MONTHS | Returns a date with a specified number of months added. |
| CURRENT_DATE | Returns the current date in the time zone of the current SQL session as set by the ALTER SESSION command. |
| CURRENT_TIMESTAMP | Returns a TIMESTAMP WITH TIME ZONE value. |
| DBTIMEZONE | Returns the database time zone as a time zone offset (in the following format: '[+|-]TZH:TZM') or a time zone region name. |
| EXTRACT | Extracts a value from a date or interval value. |
| LAST_DAY | Returns the last day of the month based on a date value. |
| LOCALTIMESTAMP | Returns the current date and time in the time zone of the current SQL session as set by the ALTER SESSION command. |
| MONTHS_BETWEEN | Returns the number of months between date1 and date2. |
| NEW_TIME | Converts a date from time zone1 to a date in time zone2. |
| NEXT_DAY | Returns the first weekday that is greater than a date. |
| ROUND (dates) | Returns a date rounded to a specific unit of measure. |
| SESSIONTIMEZONE | Returns the current session's time zone as a time zone offset (in the following format: '[+|-]TZH:TZM') or a time zone region name. |
| SYSDATE | Returns the current system date and time on your local database. |
| SYSTIMESTAMP | Returns the current system date and time on your local database. |
| TRUNC (dates) | Returns a date truncated to a specific unit of measure. |
| TZ_OFFSET | Returns the time zone offset of a value. |