postgres.git / summary / log / commit / refs
commit 1fb2d78cb94672f4cfc0c1a2da9e0a534e3698f2
Author: Michael Paquier <michael@paquier.xyz>
Date: Fri Aug 23 11:41:22 2019 +0000
First released in: 13.0, 10.11, 11.6, 12.0
Improve documentation of pageinspect
This adds a section for heap-related functions. These were previously
mixed with functions having a more general purpose, leading to
confusion. While on it, add a query example for fsm_page_contents.
Backpatch down to 10, where b5e3942 introduced the subsections for
function types in pageinspect documentation.
Author: Masahiko Sawada
Discussion: https://postgr.es/m/CAD21AoDyM7E1+cK3-aWejxKTGC-wVVP2B+RnJhN6inXyeRmqzw@mail.gmail.com
Backpatch-through: 10
doc/src/sgml/pageinspect.sgml | 56 +++++++++++++++++++++++++------------------
1 file changed, 33 insertions(+), 23 deletions(-)
diff --git a/doc/src/sgml/pageinspect.sgml b/doc/src/sgml/pageinspect.sgml
index 2ec2d957a31..442b926717c 100644
--- a/doc/src/sgml/pageinspect.sgml
+++ b/doc/src/sgml/pageinspect.sgml
@@ -125,6 +125,39 @@ test=# SELECT page_checksum(get_raw_page('pg_class', 0), 0);
</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. For example:
+<screen>
+test=# SELECT fsm_page_contents(get_raw_page('pg_class', 'fsm', 0));
+</screen>
+ 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</> 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>
@@ -203,29 +236,6 @@ 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</> for more
- information on the structure of an FSM page.
- </para>
- </listitem>
- </varlistentry>
</variablelist>
</sect2>
[parent: 73ef3df16dfa]