如何根据列中当前存在的时间值从 UTC 转换为 EST？

Question

I'd like to convert the time on both start and end columns from UTC to EST using SQL. I found the below query somewhere on the web after hours of searching for a way to do this but to no avail (the query below's incorrect).

Is there a clean way to convert from UTC to EST based on the date of the field?

start column has the current value of 2019-06-01 05:00:00

end column has the current value of 2019-06-30 04:00:00

I'd like these to be in EST timezone.

Thanks in advance.

UPDATE my_table
SET start = from_tz(to_timestamp('2009-11-17 18:40:05','yyyy-mm-dd hh24:mi:ss'), 'UTC'), end = from_tz(to_timestamp('2009-11-17 18:40:05','yyyy-mm-dd hh24:mi:ss'), 'UTC') 
AT TIME zone 'America/New_York'
WHERE id = 3;

Answer 1

You can use CONVER_TZ

you can use '+00:00' so the server hasn't to look it up, which will save time, like ysth explained in the comment

 SELECT CONVERT_TZ('2007-03-11 2:00:00','UTC','America/New_York') AS time1, CONVERT_TZ('2007-03-11 3:00:00','UTC','America/New_York') AS time2;

 time1 | time2:------------------ |:------------------ 2007-03-10 21:00:00 | 2007-03-10 22:00:00 

 UPDATE my_table SET start = CONVERT_TZ('2009-11-17 18:40:05','UTC','America/New_York'), end = CONVERT_TZ('2009-11-17 18:40:05','UTC','America/New_York') WHERE id = 3;

 Table 'db_477873842.my_table' doesn't exist

SELECT CONVERT_TZ('2007-03-11 2:00:00','+00:00','America/New_York') AS time1, CONVERT_TZ('2007-03-11 3:00:00','+00:00','America/New_York') AS time2;

 time1 | time2:------------------ |:------------------ 2007-03-10 21:00:00 | 2007-03-10 22:00:00 

 UPDATE my_table SET start = CONVERT_TZ('2009-11-17 18:40:05','+00:00','America/New_York'), end = CONVERT_TZ('2009-11-17 18:40:05','+00:00','America/New_York') WHERE id = 3;

 Table 'db_477873842.my_table' doesn't exist

db<>fiddle here