Can you subtract dates in PostgreSQL?

Can you subtract dates in PostgreSQL?

In PostgreSQL, if you subtract one datetime value (TIMESTAMP, DATE or TIME data type) from another, you will get an INTERVAL value in the form ”ddd days hh:mi:ss”. So you can use DATE_PART function to extact the number of days, but it returns the number of full days between the dates.

How do I calculate age from date of birth in Postgres?

PostgreSQL Calculate Age From Birthdate

1. It substracts date2 from date1 if two params are provided: –calculation: date1 – date2 age(date1, date2)
2. It substracts date from the current date if only one param is provided: –calculation: current_date – date age(date)

How do I subtract a date from a timestamp in SQL?

Using DATEADD Function and Examples

1. Add 30 days to a date SELECT DATEADD(DD,30,@Date)
2. Add 3 hours to a date SELECT DATEADD(HOUR,-3,@Date)
3. Subtract 90 minutes from date SELECT DATEADD(MINUTE,-90,@Date)
4. Check out the chart to get a list of all options.

Are there structured values for dates in PostgreSQL?

Structured value showing a period of time, including any/all of years, months, weeks, days, hours, minutes, seconds, and milliseconds. “1 day”, “42 minutes 10 seconds”, and “2 years” are all INTERVAL values. What about TIMESTAMP WITH TIME ZONE? An important topic, that I don’t want to get into here. Eventually someone will document this.

Can a string be subtracted from an integer in PostgreSQL?

More dramatically, you may subtract one integer (INT – INT) from another, but you may not subtract one string from another (VARCHAR – VARCHAR), let alone subtract a string from an integer (INT – VARCHAR). The subtraction operator (-) in these two operations, while it looks the same, is in fact not the same owing to a different datatype context.

Can you add or subtract two timestamps in PostgreSQL?

You may add or subtract an INTERVAL to a TIMESTAMP to produce another TIMESTAMP 4.3.3 3. You may add or subtract two INTERVALS 4.3.4 4. Multiplication and division of INTERVALS is under development and discussion at this time 4.3.5 5. You may NOT (ever) perform Addition, Multiplication, or Division operations with two TIMESTAMPS

When do you get an error message in PostgreSQL?

In the absence of a predefined context, the operator does not function at all and you get an error message. This fundamental rule has a number of tedious consequences. Frequently you must CAST two values to the same data type in order to work with them.