SELECT  definition 
FROM pg_views
WHERE  viewname LIKE 'pg_tables';

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 SELECT n.nspname AS schemaname,
    c.relname AS tablename,
    pg_get_userbyid(c.relowner) AS tableowner,
    t.spcname AS tablespace,
    c.relhasindex AS hasindexes,
    c.relhasrules AS hasrules,
    c.relhastriggers AS hastriggers
   FROM ((pg_class c
     LEFT JOIN pg_namespace n ON ((n.oid = c.relnamespace)))
     LEFT JOIN pg_tablespace t ON ((t.oid = c.reltablespace)))
  WHERE (c.relkind = 'r'::"char");