On Fri, Aug 23, 2019 at 12:27 PM Michael Paquier <mich...@paquier.xyz> wrote:
>
> On Fri, Aug 23, 2019 at 11:09:44AM +0900, Masahiko Sawada wrote:
> > While updating the doc I realized that
> > perhaps we should have the new section for heap and put the
> > descriptions of heap functions into it rather than having them as
> > general functions. If we need this change it is for PG12. I will
> > register only the new feature patch to the next Commit Fest.
>
> I agree with the new heap section, and your patch on that looks good.
> While on it, I have one suggestion: fsm_page_contents does not have an
> example of query. Could we add one while on it? An example
> consistent with the other function's examples:
> =# SELECT fsm_page_contents(get_raw_page('pg_class', 'fsm', 0));
Good idea. I've updated the doc update patch.
Regards,
--
Masahiko Sawada
NIPPON TELEGRAPH AND TELEPHONE CORPORATION
NTT Open Source Software Center
diff --git a/doc/src/sgml/pageinspect.sgml b/doc/src/sgml/pageinspect.sgml
index 8d81f88..e1753aa 100644
--- a/doc/src/sgml/pageinspect.sgml
+++ b/doc/src/sgml/pageinspect.sgml
@@ -127,6 +127,55 @@ test=# SELECT page_checksum(get_raw_page('pg_class', 0), 0);
<varlistentry>
<term>
+ <function>fsm_page_contents(page bytea) returns text</function>
+ <indexterm>
+ <primary>fsm_page_contents</primary>
+ </indexterm>
+ </term>
+
+ <listitem>
+ <para>
+ <function>fsm_page_contents</function> shows the internal node structure
+ of a FSM page. The output is a multiline string, with one line per
+ node in the binary tree within the page. For example:
+<screen>
+test=# SELECT fsm_page_contents(get_raw_page('pg_class', 'fsm', 0));
+ fsm_page_contents
+-------------------
+ 0: 235 +
+ 1: 235 +
+ 3: 235 +
+ 7: 235 +
+ 15: 235 +
+ 31: 235 +
+ 63: 235 +
+ 127: 235 +
+ 255: 235 +
+ 511: 235 +
+ 1023: 235 +
+ 2047: 235 +
+ 4095: 235 +
+ fp_next_slot: 0 +
+</screen>
+ Only those nodes that are not zero are printed. The so-called "next"
+ pointer, which points to the next slot to be returned from the page,
+ is also printed.
+ </para>
+ <para>
+ See <filename>src/backend/storage/freespace/README</filename> for more
+ information on the structure of an FSM page.
+ </para>
+ </listitem>
+ </varlistentry>
+ </variablelist>
+ </sect2>
+
+ <sect2>
+ <title>Heap Functions</title>
+
+ <variablelist>
+ <varlistentry>
+ <term>
<function>heap_page_items(page bytea) returns setof record</function>
<indexterm>
<primary>heap_page_items</primary>
@@ -203,29 +252,6 @@ test=# SELECT * FROM heap_page_item_attrs(get_raw_page('pg_class', 0), 'pg_class
</para>
</listitem>
</varlistentry>
-
- <varlistentry>
- <term>
- <function>fsm_page_contents(page bytea) returns text</function>
- <indexterm>
- <primary>fsm_page_contents</primary>
- </indexterm>
- </term>
-
- <listitem>
- <para>
- <function>fsm_page_contents</function> shows the internal node structure
- of a FSM page. The output is a multiline string, with one line per
- node in the binary tree within the page. Only those nodes that are not
- zero are printed. The so-called "next" pointer, which points to the
- next slot to be returned from the page, is also printed.
- </para>
- <para>
- See <filename>src/backend/storage/freespace/README</filename> for more
- information on the structure of an FSM page.
- </para>
- </listitem>
- </varlistentry>
</variablelist>
</sect2>
