From 4c685d4990dbf641914175628db1ba74ac3cabfa Mon Sep 17 00:00:00 2001
From: kommih <haribabuk@fast.au.fujitsu.com>
Date: Thu, 7 Feb 2019 16:21:40 +1100
Subject: [PATCH 03/17] Reorganize am as both table and index

There is not much table access methods info.
---
 doc/src/sgml/am.sgml | 61 +++++++++++++++++++++++++++++---------------
 1 file changed, 41 insertions(+), 20 deletions(-)

diff --git a/doc/src/sgml/am.sgml b/doc/src/sgml/am.sgml
index a9f0838ee5..579187ed1b 100644
--- a/doc/src/sgml/am.sgml
+++ b/doc/src/sgml/am.sgml
@@ -1,16 +1,34 @@
 <!-- doc/src/sgml/am.sgml -->
 
-<chapter id="indexam">
- <title>Index Access Method Interface Definition</title>
+<chapter id="am">
+ <title>Access Method Interface Definition</title>
 
   <para>
    This chapter defines the interface between the core
-   <productname>PostgreSQL</productname> system and <firstterm>index access
-   methods</firstterm>, which manage individual index types.  The core system
-   knows nothing about indexes beyond what is specified here, so it is
-   possible to develop entirely new index types by writing add-on code.
-  </para>
-
+   <productname>PostgreSQL</productname> system and <firstterm>access
+   methods</firstterm>, which manage individual <literal>INDEX</literal> 
+   and <literal>TABLE</literal> types.  The core system knows nothing
+   about these access methods beyond what is specified here, so it is
+   possible to develop entirely new access method types by writing add-on code.
+  </para>
+ 
+ <sect1 id="table-access-methods">
+  <title>Overview of Table access methods </title>
+  
+  <para>
+   All Tables in <productname>PostgreSQL</productname> are the primary
+   data store. Each table is stored as its own physical <firstterm>relation</firstterm>
+   and so is described by an entry in the <structname>pg_class</structname>
+   catalog. The contents of an table are entirely under the control of its
+   access method. (All the access methods furthermore use the standard page
+   layout described in <xref linkend="storage-page-layout"/>.)
+  </para>
+
+ </sect1> 
+ 
+ <sect1 id="index-access-methods">
+  <title>Overview of Index access methods</title>
+  
   <para>
    All indexes in <productname>PostgreSQL</productname> are what are known
    technically as <firstterm>secondary indexes</firstterm>; that is, the index is
@@ -42,8 +60,8 @@
    dead tuples are reclaimed (by vacuuming) when the dead tuples themselves
    are reclaimed.
   </para>
-
- <sect1 id="index-api">
+  
+ <sect2 id="index-api">
   <title>Basic API Structure for Indexes</title>
 
   <para>
@@ -217,9 +235,9 @@ typedef struct IndexAmRoutine
    conditions.
   </para>
 
- </sect1>
+ </sect2>
 
- <sect1 id="index-functions">
+ <sect2 id="index-functions">
   <title>Index Access Method Functions</title>
 
   <para>
@@ -710,9 +728,11 @@ amparallelrescan (IndexScanDesc scan);
    the beginning.
   </para>
 
- </sect1>
+ </sect2>
+ 
+ 
 
- <sect1 id="index-scanning">
+ <sect2 id="index-scanning">
   <title>Index Scanning</title>
 
   <para>
@@ -865,9 +885,9 @@ amparallelrescan (IndexScanDesc scan);
    if its internal implementation is unsuited to one API or the other.
   </para>
 
- </sect1>
+ </sect2>
 
- <sect1 id="index-locking">
+ <sect2 id="index-locking">
   <title>Index Locking Considerations</title>
 
   <para>
@@ -979,9 +999,9 @@ amparallelrescan (IndexScanDesc scan);
    reduce the frequency of such transaction cancellations.
   </para>
 
- </sect1>
+ </sect2>
 
- <sect1 id="index-unique-checks">
+ <sect2 id="index-unique-checks">
   <title>Index Uniqueness Checks</title>
 
   <para>
@@ -1128,9 +1148,9 @@ amparallelrescan (IndexScanDesc scan);
     </itemizedlist>
   </para>
 
- </sect1>
+ </sect2>
 
- <sect1 id="index-cost-estimation">
+ <sect2 id="index-cost-estimation">
   <title>Index Cost Estimation Functions</title>
 
   <para>
@@ -1377,5 +1397,6 @@ cost_qual_eval(&amp;index_qual_cost, path-&gt;indexquals, root);
    Examples of cost estimator functions can be found in
    <filename>src/backend/utils/adt/selfuncs.c</filename>.
   </para>
+ </sect2>
  </sect1>
 </chapter>
-- 
2.20.1.windows.1