ERROR: function convert_timezone("unknown", "unknown", timestamp with time zone) does not exist

Question

I have a column with datatype "timestamp with time zone" in UTC. I want to convert it to EST while accounting for daylight savings time. If we call the column [col1], I have tried the query as "convert_timezone('UTC','EST',col1) " and "convert_timezone('UTC','EDT',col1) ". When I run this, I receive this error message: "ERROR: function convert_timezone("unknown", "unknown", timestamp with time zone) does not exist Hint: No function matches the given name and argument types. You may need to add explicit type casts. [ErrorId: 1-664f48e0-729d308e6412d4d328c6a041]". 
For context, I tried the "TIMEZONE" function as well, which runs without error but does not account for daylight savings time.

JackieE · Answer

To convert a "timestamp with time zone" column in UTC to EST while accounting for daylight savings time in Amazon Redshift.

You can also use the AT TIME ZONE  function to convert the UTC timestamp to EST:

SELECT column_name AT TIME ZONE 'UTC' AT TIME ZONE 'EST'
FROM your_table;

However you should be able to use CONVERT_TIMEZONE function to achieve the same result:
I have done some basic testing and got the result below.

![Enter image description here](/media/postImages/original/IMz4niv0wWRhaTVkcyXNTz8g)

ERROR: function convert_timezone("unknown", "unknown", timestamp with time zone) does not exist

Relevant content