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

As Yaniv Kessler mentioned, it's not possible to add or change distkey and sort key after creating a table, and you have to recreate a table and copy all data to the new table. You can use the following SQL format to recreate a table with a new design.

ALTER TABLE test_table RENAME TO old_test_table;
CREATE TABLE new_test_table([new table columns]);
INSERT INTO new_test_table (SELECT * FROM old_test_table);
ALTER TABLE new_test_table RENAME TO test_table;
DROP TABLE old_test_table;

In my experience, this SQL is used for not only changing distkey and sortkey, but also setting the encoding(compression) type.