Showing Redshift Distkey & Sortkey

October 26, 2015

One slightly unfortunate aspect of how Postgres interacts with Redshift is that standard tooling like \d+ can’t be used to inspect a table’s distkey or sortkey. As such, the recommended way of showing these is by querying the pg_table_def table.

SELECT "column", type, distkey, sortkey
FROM pg_table_def
WHERE schemaname = 'logs' AND
    tablename = 'bapi' 
AND distkey = true
    OR sortkey <> 0;

 column  |            type             | distkey | sortkey
---------+-----------------------------+---------+---------
 created | timestamp without time zone | f       |       1

But wait! There’s one more gotcha here to think about. As described in the documentation, only schemas that are contained in the user’s search_path will be shown in pg_table_def. If you try to query for a table outside of a search_path schema, it may mysteriously come up empty. Make sure to set search_path like so:

set search_path to '$user', infra, logs, public;

(And recall that this can go into your ~/.psqlrc.)

Showing Redshift Distkey & Sortkey was published on October 26, 2015.

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