Select all relations in PostgreSQL

tl;dr Start psql with -E or --echo-hidden

I wanted to find out EVERYTHING that's related to a specific topic. Tables, views, stored procedures etc.
One way of doing that is to go into psql and type \d and/or \df and look through that list. But that's unpractical if it gets large and I might want to get it out stdout instead so I can grep and grep -v.

There are lots of Stackoverflow questions about how to SQL select all tables but I want it all. The solution is to start psql with -E or --echo-hidden. When you do that, it prints out what SQL it used to generate the output for you there. You can then copy that and do whatever you want to do with it. For example:

peterbecom=# \d
********* QUERY **********
SELECT n.nspname as "Schema",
  c.relname as "Name",
  CASE c.relkind WHEN 'r' THEN 'table' WHEN 'v' THEN 'view' WHEN 'm' THEN 'materialized view' WHEN 'i' THEN 'index' WHEN 'S' THEN 'sequence' WHEN 's' THEN 'special' WHEN 'f' THEN 'foreign table' END as "Type",
  pg_catalog.pg_get_userbyid(c.relowner) as "Owner"
FROM pg_catalog.pg_class c
     LEFT JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespace
WHERE c.relkind IN ('r','v','m','S','f','')
      AND n.nspname <> 'pg_catalog'
      AND n.nspname <> 'information_schema'
      AND n.nspname !~ '^pg_toast'
  AND pg_catalog.pg_table_is_visible(c.oid)
ORDER BY 1,2;
**************************

With this I was able to come up with this SQL select to get all tables, views, sequences and functions.

SELECT
  c.relname as "Name",
  CASE c.relkind WHEN 'r' THEN 'table'
  WHEN 'v' THEN 'view'
  WHEN 'm' THEN 'materialized view'
  WHEN 'i' THEN 'index'
  WHEN 'S' THEN 'sequence'
  WHEN 's' THEN 'special'
  WHEN 'f' THEN 'foreign table' END as "Type"
FROM pg_catalog.pg_class c
     LEFT JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespace
WHERE c.relkind IN ('r','v','m','S','f','')
      AND n.nspname <> 'pg_catalog'
      AND n.nspname <> 'information_schema'
      AND n.nspname !~ '^pg_toast'
  AND pg_catalog.pg_table_is_visible(c.oid);


SELECT
  p.proname as "Name",
  'function'
FROM pg_catalog.pg_proc p
     LEFT JOIN pg_catalog.pg_namespace n ON n.oid = p.pronamespace
WHERE pg_catalog.pg_function_is_visible(p.oid)
      AND n.nspname <> 'pg_catalog'
      AND n.nspname <> 'information_schema';

A usecase of this is that I put those two SQL selects in a file and now I can grep:

$ psql mydatabase < everything.sql | grep -i crap