sqlpostgresqltimestamp-with-timezone

SQL: function trunc(timestamp without time zone, "unknown") does not exist

I am trying to transform a date column to week by using the following code:

select trunc(join_date, 'D') as join_wk from my_table

But I got the following errors:

function trunc(timestamp without time zone, "unknown") does not exist
  Hint: No function matches the given name and argument types. You may need to add explicit type casts.

where join_date is of the format: 

2017-08-24 14:49:59

What did I do wrong in the query? Thanks!

Solution

  • The name of the function is date_trunc, you have to swap the parameters:

    SELECT DATE_TRUNC('D', join_date) AS join_wk FROM my_table