postgres column값을 interval에 다이나믹하게 사용하는 방법

https://stackoverflow.com/questions/5266758/dynamic-column-based-interval

Dynamic (Column Based) Interval

 

I know this is a year old, but if you need to use a column to specify the actual interval (e.g. 'days', 'months', then it is worth knowing that you can also CAST your string to an Interval, giving:

SELECT now()+ CAST(the_duration||' '||the_interval AS Interval)

 

SELECT now() + CAST(a.number_of_days||" DAYS" AS Interval) as "The Future Date" FROM a;