Show The Hidden Queries Behind Backslash Commands

The ECHO_HIDDEN variable in PostgreSQL’s psql determines whether the queries behind backslash commands are displayed. It defaults to false. So, generally, when you run something like \d or \l+, you’ll just see the result and not the query that helped produce it.

If you’re curious what’s behind any of these backslash commands, then set ECHO_HIDDEN to true to get a look.

> \set ECHO_HIDDEN true
> \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' WHEN 'p' THEN 'partitioned table' WHEN 'I' THEN 'partitioned index' 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','p','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;
**************************

               List of relations
 Schema |     Name     |   Type   |   Owner
--------+--------------+----------+------------
 public | users        | table    | jbranchaud
 public | users_id_seq | sequence | jbranchaud

That query is what psql uses to list the relations for your current database.

[postgres@pgcm1 ~]$ psql -E
psql (18.6)
Type "help" for help.

postgres=# \l
/******** QUERY *********/
SELECT
  d.datname as "Name",
  pg_catalog.pg_get_userbyid(d.datdba) as "Owner",
  pg_catalog.pg_encoding_to_char(d.encoding) as "Encoding",
  CASE d.datlocprovider WHEN 'b' THEN 'builtin' WHEN 'c' THEN 'libc' WHEN 'i' THEN 'icu' END AS "Locale Provider",
  d.datcollate as "Collate",
  d.datctype as "Ctype",
  d.datlocale as "Locale",
  d.daticurules as "ICU Rules",
  CASE WHEN pg_catalog.array_length(d.datacl, 1) = 0 THEN '(none)' ELSE pg_catalog.array_to_string(d.datacl, E'\n') END AS "Access privileges"
FROM pg_catalog.pg_database d
ORDER BY 1;
/************************/

                                                List of databases
   Name    |  Owner   | Encoding | Locale Provider | Collate | Ctype | Locale | ICU Rules |   Access privileges   
-----------+----------+----------+-----------------+---------+-------+--------+-----------+-----------------------
 postgres  | postgres | UTF8     | libc            | C       | C     |        |           | 
 template0 | postgres | UTF8     | libc            | C       | C     |        |           | =c/postgres          +
           |          |          |                 |         |       |        |           | postgres=CTc/postgres
 template1 | postgres | UTF8     | libc            | C       | C     |        |           | =c/postgres          +
           |          |          |                 |         |       |        |           | postgres=CTc/postgres
(3 rows)

postgres=# exit
[postgres@pgcm1 ~]$ 
[postgres@pgcm1 ~]$ psql
psql (18.6)
Type "help" for help.

postgres=# \dt
/******** 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 't' THEN 'TOAST table' WHEN 'f' THEN 'foreign table' WHEN 'p' THEN 'partitioned table' WHEN 'I' THEN 'partitioned index' 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
     LEFT JOIN pg_catalog.pg_am am ON am.oid = c.relam
WHERE c.relkind IN ('r','p','v','m','S','f','')
      AND n.nspname <> 'pg_catalog'
      AND n.nspname !~ '^pg_toast'
      AND n.nspname <> 'information_schema'
  AND pg_catalog.pg_table_is_visible(c.oid)
ORDER BY 1,2;
/************************/

Did not find any relations.
postgres=#