refahour.blogg.se - Chicago vs new york time zone

SELECT ' 07:09:19- 10':: timestamp AT TIME ZONE 'America/Chicago' SELECT ' 07:09:19':: timestamp AT TIME ZONE 'America/Chicago' This behavior is also shown in AT TIME ZONE: This is because casting a value to TIMESTAMP WITHOUT TIME ZONE ignores any specified time zone: It doesn't matter if a time zone designation is specified in the ::timestamp string - only the date and time are used. What is basically happening above is that the date and time are interpreted as being in the specified time zone (e.g., America/Chicago), a TIMESTAMP WITH TIME ZONE value is created, and the value displayed in the default time zone ( -04). SELECT ' 07:09:19':: timestamp AT TIME ZONE ' Asia/Tokyo'

SELECT ' 07:09:19':: timestamp AT TIME ZONE ' America/Los_Angeles' SELECT ' 07:09:19':: timestamp AT TIME ZONE ' America/Chicago' First, let's see #1, AT TIME ZONE adding time zone designations: It is kind of odd for AT TIME ZONE to be used for both purposes, but the SQL standard requires this.

TIMESTAMP WITH TIME ZONE ⇾ TIMESTAMP WITHOUT TIME ZONE (shift time zone).

TIMESTAMP WITHOUT TIME ZONE ⇾ TIMESTAMP WITH TIME ZONE (add time zone).

It allows time zones to be added to date/time values that lack them (TIMESTAMP WITHOUT TIME ZONE, ::timestamp), and allows TIMESTAMP WITH TIME ZONE values ( ::timestamp tz) to be shifted to non-local time zones and the time zone designation removed. I then updated the Postgres documentation to explain it better, and here is what I found.įirst, AT TIME ZONE has two capabilities. I read the Postgres documentation and was still confused, so I played with some queries and finally figured it out. I saw AT TIME ZONE used in a query, and found it confusing.