How to add a sort key to an existing table in AWS Redshift

Question

In AWS Redshift, I want to add a sort key to a table that is already created. Is there any command which can add a column and use it as sort key?

Answer 1

To add to Yaniv's answer, the ideal way to do this is probably using the CREATE TABLE AS command. You can specify the distkey and sortkey explicitly. I.e.

CREATE TABLE test_table_with_dist 
distkey(field) 
sortkey(sortfield) 
AS 
select * from test_table

Additional examples:

http://docs.aws.amazon.com/redshift/latest/dg/r_CTAS_examples.html

EDIT

I've noticed that this method doesn't preserve encoding. Redshift only automatically encodes during a copy statement. If this is a persistent table you should redefine the table and specify the encoding.

create table test_table_with_dist(
    field1 varchar encode row distkey
    field2 timestam pencode delta sortkey);

insert into test_table select * from test_table;

You can figure out which encoding to use by running analyze compression test_table;