Re: Have \d show child tables that inherit from the specified parent - Mailing list pgsql-hackers

Hi,

Here's a second version. Main changes are :

* Child tables are sorted by name
* \d only shows the number of child tables
* \d+ shows the full list

Which gives :

postgres=# \d mother
                         Table "public.mother"
 Column |  Type   |                      Modifiers
--------+---------+-----------------------------------------------------
 id     | integer | not null default nextval('mother_id_seq'::regclass)
This table has 4 child table(s). Use \d+ to display them.

postgres=# \d+ mother
                                     Table "public.mother"
 Column |  Type   |                      Modifiers
| Storage | Description
--------+---------+-----------------------------------------------------+---------+-------------
 id     | integer | not null default nextval('mother_id_seq'::regclass)
| plain   |
Child tables: daughter,
              daughter2,
              daughter3,
              plop.daughter4
Has OIDs: no


For people having hundreds of child tables, the use of \d+ will still be
uncomfortable. But i must admit that i can't see any better way to
implement this feature, except by adding a new syntax ( \dh to show
specific information about inheritance ? )

Anyway let me know if you think it is not worth going forward on that
feature :-)

--
damien clochard
http://dalibo.org | http://dalibo.com
? logfile
Index: describe.c
===================================================================
RCS file: /projects/cvsroot/pgsql/src/bin/psql/describe.c,v
retrieving revision 1.212
diff -c -r1.212 describe.c
*** describe.c    5 May 2009 02:29:06 -0000    1.212
--- describe.c    9 May 2009 23:57:36 -0000
***************
*** 1812,1817 ****
--- 1812,1856 ----
          }
          PQclear(result);

+         /* print child tables */
+         printfPQExpBuffer(&buf, "SELECT c.oid::pg_catalog.regclass FROM pg_catalog.pg_class c, pg_catalog.pg_inherits
iWHERE c.oid=i.inhrelid AND i.inhparent = '%s'  ORDER BY c.oid::pg_catalog.regclass;", oid); 
+
+         result = PSQLexec(buf.data, false);
+         if (!result)
+             goto error_return;
+         else
+             tuples = PQntuples(result);
+
+         if (!verbose)
+         {
+             /* print the number of child tables, if any */
+             if (tuples > 0)
+             {
+                 printfPQExpBuffer(&buf, _("This table has %i child table(s). Use \\d+ to display them."),tuples);
+                 printTableAddFooter(&cont, buf.data);
+             }
+         }
+         else
+         {
+             /* display the list of child tables*/
+             for (i = 0; i < tuples; i++)
+                     {
+                             const char *ct = _("Child tables");
+
+                             if (i == 0)
+                                     printfPQExpBuffer(&buf, "%s: %s", ct, PQgetvalue(result, i, 0));
+                             else
+                                     printfPQExpBuffer(&buf, "%*s  %s", (int) strlen(ct), "", PQgetvalue(result, i,
0));
+                             if (i < tuples - 1)
+                                     appendPQExpBuffer(&buf, ",");
+
+                             printTableAddFooter(&cont, buf.data);
+                     }
+         }
+         PQclear(result);
+
+
+
          if (verbose)
          {
              const char *s = _("Has OIDs");