YYYY-MM column type in PostgreSQL

Question

I need to a value associated to a month and a user in a table. And I want to perform queries on it. I don\'t know if there is a column data type for this type of need. If no

Answer 1

I would suggest not thinking too hard about the problem and just using the first date/time of the month. Postgres has plenty of date-specific functions -- from date_trunc() to age() to + interval -- to support dates.

You can readily convert them to the format you want, get the difference between two values, and so on.

If you phrase your query as:

where year_month = date_trunc('month', now()) and user_id = 'adc1-23...'

Then it can readily take advantage of an index on (user_id, year_month) or (year_month, user_id).

Answer 2

If you are interested in display values in YYYY-MM formt you can use to_char(your_datatime_colum,'YYYY-MM')

example:

SELECT to_char(now(),'YYYY-MM') as year_month