Date, Time, Age
The NOW function returns the current date and time, but can be scoped to retrieved the individual fields.
In addition, arithmetic operation can be applied to NOW using the INTERVAL function.
AGE can be calculated from the date of birth (DOB).
| Syntax | Description |
|---|---|
SELECT NOW(); |
The current date and time. |
SELECT NOW()::DATE; |
The current date. |
SELECT NOW()::TIME; |
The current time. |
SELECT AGE(NOW(), < DOB >); |
The age based on date of birth. |
Date Arithmetic
Date arithmetic can be done using the following intervals:
YEAR, YEARS, MONTH, MONTHS, DAY and DAY.
| Example | Description |
|---|---|
SELECT NOW() - INTERVAL '1 YEAR'; |
The date and time one year ago. |
SELECT (NOW() + INTERVAL '10 MONTHS'); |
The date in ten months. |
Extract
The EXTRACT function extracts parts from a date. NOW is the date used in the examples.
| Example | Description |
|---|---|
SELECT EXTRACT(CENTURY FROM NOW()); |
The current century. |
SELECT EXTRACT(YEAR FROM NOW()); |
The current year. |
SELECT EXTRACT(MONTH FROM NOW()); |
The current month. |
SELECT EXTRACT(DAY FROM NOW()); |
The current day. |
SELECT EXTRACT(DOW FROM NOW()); |
The current day of week. |