Re: [PATCH] Add section headings to index types doc - Mailing list pgsql-hackers

Michael Paquier <michael@paquier.xyz> writes:

> On Mon, Aug 10, 2020 at 12:52:17PM +0000, Jürgen Purtz wrote:
>> The new status of this patch is: Waiting on Author
>
> This has not been answered yet, so I have marked the patch as returned
> with feedback.

Updated patch attached, wich reformats the operator lists as requested
by Jürgen, and skips the reindentation as suggested by Tom.

The reindentation patch is attached separately, in case the committer
decides they want it properly indented after all.

- ilmari
-- 
- Twitter seems more influential [than blogs] in the 'gets reported in
  the mainstream press' sense at least.               - Matt McLeod
- That'd be because the content of a tweet is easier to condense down
  to a mainstream media article.                      - Calle Dybedahl

From 84522dc77afd1b8ce0bf111279302888d9d3edcb Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Dagfinn=20Ilmari=20Manns=C3=A5ker?= <ilmari@ilmari.org>
Date: Fri, 31 Jul 2020 10:20:48 +0100
Subject: [PATCH] Add section headers to index types doc

This makes it easier to compare the properties of different index
types at a glance.

In passing, make the index operator lists a single line each.
---
 doc/src/sgml/indices.sgml | 81 +++++++++++++++++++--------------------
 1 file changed, 39 insertions(+), 42 deletions(-)

diff --git a/doc/src/sgml/indices.sgml b/doc/src/sgml/indices.sgml
index 671299ff05..f22253f4c3 100644
--- a/doc/src/sgml/indices.sgml
+++ b/doc/src/sgml/indices.sgml
@@ -122,6 +122,9 @@
    B-tree indexes, which fit the most common situations.
   </para>
 
+  <sect2 id="indexes-types-btree">
+   <title>B-tree</title>
+
   <para>
    <indexterm>
     <primary>index</primary>
@@ -137,13 +140,9 @@
    will consider using a B-tree index whenever an indexed column is
    involved in a comparison using one of these operators:
 
-   <simplelist>
-    <member><literal><</literal></member>
-    <member><literal><=</literal></member>
-    <member><literal>=</literal></member>
-    <member><literal>>=</literal></member>
-    <member><literal>></literal></member>
-   </simplelist>
+<synopsis>
+<   <=   =   >=   >
+</synopsis>
 
    Constructs equivalent to combinations of these operators, such as
    <literal>BETWEEN</literal> and <literal>IN</literal>, can also be implemented with
@@ -172,6 +171,10 @@
    This is not always faster than a simple scan and sort, but it is
    often helpful.
   </para>
+  </sect2>
+
+  <sect2 id="indexes-types-hash">
+   <title>Hash</title>
 
   <para>
    <indexterm>
@@ -191,6 +194,10 @@
 CREATE INDEX <replaceable>name</replaceable> ON <replaceable>table</replaceable> USING HASH
(<replaceable>column</replaceable>);
 </synopsis>
   </para>
+  </sect2>
+
+  <sect2 id="indexes-type-gist">
+   <title>GiST</title>
 
   <para>
    <indexterm>
@@ -210,20 +217,9 @@
    for several two-dimensional geometric data types, which support indexed
    queries using these operators:
 
-   <simplelist>
-    <member><literal><<</literal></member>
-    <member><literal>&<</literal></member>
-    <member><literal>&></literal></member>
-    <member><literal>>></literal></member>
-    <member><literal><<|</literal></member>
-    <member><literal>&<|</literal></member>
-    <member><literal>|&></literal></member>
-    <member><literal>|>></literal></member>
-    <member><literal>@></literal></member>
-    <member><literal><@</literal></member>
-    <member><literal>~=</literal></member>
-    <member><literal>&&</literal></member>
-   </simplelist>
+<synopsis>
+<<   &<   &>   >>   <<|   &<|   |&>  
|>>  @>   <@   ~=   &&
 
+</synopsis>
 
    (See <xref linkend="functions-geometry"/> for the meaning of
    these operators.)
@@ -246,6 +242,10 @@
    In <xref linkend="gist-builtin-opclasses-table"/>, operators that can be
    used in this way are listed in the column <quote>Ordering Operators</quote>.
   </para>
+  </sect2>
+
+  <sect2 id="indexes-type-spgist">
+   <title>SP-GiST</title>
 
   <para>
    <indexterm>
@@ -264,14 +264,9 @@
    for two-dimensional points, which support indexed
    queries using these operators:
 
-   <simplelist>
-    <member><literal><<</literal></member>
-    <member><literal>>></literal></member>
-    <member><literal>~=</literal></member>
-    <member><literal><@</literal></member>
-    <member><literal><^</literal></member>
-    <member><literal>>^</literal></member>
-   </simplelist>
+<synopsis>
+<<   >>   ~=   <@   <^   >^
+</synopsis>
 
    (See <xref linkend="functions-geometry"/> for the meaning of
    these operators.)
@@ -286,6 +281,10 @@
    corresponding operator is specified in the <quote>Ordering Operators</quote>
    column in <xref linkend="spgist-builtin-opclasses-table"/>.
   </para>
+  </sect2>
+
+  <sect2 id="indexes-types-gin">
+   <title>GIN</title>
 
   <para>
    <indexterm>
@@ -312,12 +311,9 @@
    <productname>PostgreSQL</productname> includes a GIN operator class
    for arrays, which supports indexed queries using these operators:
 
-   <simplelist>
-    <member><literal><@</literal></member>
-    <member><literal>@></literal></member>
-    <member><literal>=</literal></member>
-    <member><literal>&&</literal></member>
-   </simplelist>
+<synopsis>
+<@   @>   =   &&
+</synopsis>
 
    (See <xref linkend="functions-array"/> for the meaning of
    these operators.)
@@ -327,6 +323,10 @@
    classes are available in the <literal>contrib</literal> collection or as separate
    projects.  For more information see <xref linkend="gin"/>.
   </para>
+  </sect2>
+
+  <sect2 id="indexes-types-brin">
+   <title>BRIN</title>
 
   <para>
    <indexterm>
@@ -348,18 +348,15 @@
    values in the column for each block range.  This supports indexed queries
    using these operators:
 
-   <simplelist>
-    <member><literal><</literal></member>
-    <member><literal><=</literal></member>
-    <member><literal>=</literal></member>
-    <member><literal>>=</literal></member>
-    <member><literal>></literal></member>
-   </simplelist>
+<synopsis>
+<   <=   =   >=   >
+</synopsis>
 
    The BRIN operator classes included in the standard distribution are
    documented in <xref linkend="brin-builtin-opclasses-table"/>.
    For more information see <xref linkend="brin"/>.
   </para>
+  </sect2>
  </sect1>
 
 
-- 
2.27.0

From 2a75f535e60e89ed7e2276f4775395162f364e8c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Dagfinn=20Ilmari=20Manns=C3=A5ker?= <ilmari@ilmari.org>
Date: Tue, 1 Sep 2020 11:48:59 +0100
Subject: [PATCH 2/2] Reindent index types docs after previous commit

The previous commit wrapped each index type descripiton in a `<sect2>`
tag, but avoided reidenting for ease of review.  This commit reindents
everything, except the `<synopsis>` and `<programlisting>` tags, which
appear to need to be in column zero.
---
 doc/src/sgml/indices.sgml | 338 +++++++++++++++++++-------------------
 1 file changed, 169 insertions(+), 169 deletions(-)

diff --git a/doc/src/sgml/indices.sgml b/doc/src/sgml/indices.sgml
index f22253f4c3..3e11d3917f 100644
--- a/doc/src/sgml/indices.sgml
+++ b/doc/src/sgml/indices.sgml
@@ -125,237 +125,237 @@
   <sect2 id="indexes-types-btree">
    <title>B-tree</title>
 
-  <para>
-   <indexterm>
-    <primary>index</primary>
-    <secondary>B-tree</secondary>
-   </indexterm>
-   <indexterm>
-    <primary>B-tree</primary>
-    <see>index</see>
-   </indexterm>
-   B-trees can handle equality and range queries on data that can be sorted
-   into some ordering.
-   In particular, the <productname>PostgreSQL</productname> query planner
-   will consider using a B-tree index whenever an indexed column is
-   involved in a comparison using one of these operators:
+   <para>
+    <indexterm>
+     <primary>index</primary>
+     <secondary>B-tree</secondary>
+    </indexterm>
+    <indexterm>
+     <primary>B-tree</primary>
+     <see>index</see>
+    </indexterm>
+    B-trees can handle equality and range queries on data that can be sorted
+    into some ordering.
+    In particular, the <productname>PostgreSQL</productname> query planner
+    will consider using a B-tree index whenever an indexed column is
+    involved in a comparison using one of these operators:
 
 <synopsis>
 <   <=   =   >=   >
 </synopsis>
 
-   Constructs equivalent to combinations of these operators, such as
-   <literal>BETWEEN</literal> and <literal>IN</literal>, can also be implemented with
-   a B-tree index search.  Also, an <literal>IS NULL</literal> or <literal>IS NOT
-   NULL</literal> condition on an index column can be used with a B-tree index.
-  </para>
+    Constructs equivalent to combinations of these operators, such as
+    <literal>BETWEEN</literal> and <literal>IN</literal>, can also be implemented with
+    a B-tree index search.  Also, an <literal>IS NULL</literal> or <literal>IS NOT
+    NULL</literal> condition on an index column can be used with a B-tree index.
+   </para>
 
-  <para>
-   The optimizer can also use a B-tree index for queries involving the
-   pattern matching operators <literal>LIKE</literal> and <literal>~</literal>
-   <emphasis>if</emphasis> the pattern is a constant and is anchored to
-   the beginning of the string — for example, <literal>col LIKE
-   'foo%'</literal> or <literal>col ~ '^foo'</literal>, but not
-   <literal>col LIKE '%bar'</literal>. However, if your database does not
-   use the C locale you will need to create the index with a special
-   operator class to support indexing of pattern-matching queries; see
-   <xref linkend="indexes-opclass"/> below. It is also possible to use
-   B-tree indexes for <literal>ILIKE</literal> and
-   <literal>~*</literal>, but only if the pattern starts with
-   non-alphabetic characters, i.e., characters that are not affected by
-   upper/lower case conversion.
-  </para>
+   <para>
+    The optimizer can also use a B-tree index for queries involving the
+    pattern matching operators <literal>LIKE</literal> and <literal>~</literal>
+    <emphasis>if</emphasis> the pattern is a constant and is anchored to
+    the beginning of the string — for example, <literal>col LIKE
+    'foo%'</literal> or <literal>col ~ '^foo'</literal>, but not
+    <literal>col LIKE '%bar'</literal>. However, if your database does not
+    use the C locale you will need to create the index with a special
+    operator class to support indexing of pattern-matching queries; see
+    <xref linkend="indexes-opclass"/> below. It is also possible to use
+    B-tree indexes for <literal>ILIKE</literal> and
+    <literal>~*</literal>, but only if the pattern starts with
+    non-alphabetic characters, i.e., characters that are not affected by
+    upper/lower case conversion.
+   </para>
 
-  <para>
-   B-tree indexes can also be used to retrieve data in sorted order.
-   This is not always faster than a simple scan and sort, but it is
-   often helpful.
-  </para>
+   <para>
+    B-tree indexes can also be used to retrieve data in sorted order.
+    This is not always faster than a simple scan and sort, but it is
+    often helpful.
+   </para>
   </sect2>
 
   <sect2 id="indexes-types-hash">
    <title>Hash</title>
 
-  <para>
-   <indexterm>
-    <primary>index</primary>
-    <secondary>hash</secondary>
-   </indexterm>
-   <indexterm>
-    <primary>hash</primary>
-    <see>index</see>
-   </indexterm>
-   Hash indexes can only handle simple equality comparisons.
-   The query planner will consider using a hash index whenever an
-   indexed column is involved in a comparison using the
-   <literal>=</literal> operator.
-   The following command is used to create a hash index:
+   <para>
+    <indexterm>
+     <primary>index</primary>
+     <secondary>hash</secondary>
+    </indexterm>
+    <indexterm>
+     <primary>hash</primary>
+     <see>index</see>
+    </indexterm>
+    Hash indexes can only handle simple equality comparisons.
+    The query planner will consider using a hash index whenever an
+    indexed column is involved in a comparison using the
+    <literal>=</literal> operator.
+    The following command is used to create a hash index:
 <synopsis>
 CREATE INDEX <replaceable>name</replaceable> ON <replaceable>table</replaceable> USING HASH
(<replaceable>column</replaceable>);
 </synopsis>
-  </para>
+   </para>
   </sect2>
 
   <sect2 id="indexes-type-gist">
    <title>GiST</title>
 
-  <para>
-   <indexterm>
-    <primary>index</primary>
-    <secondary>GiST</secondary>
-   </indexterm>
-   <indexterm>
-    <primary>GiST</primary>
-    <see>index</see>
-   </indexterm>
-   GiST indexes are not a single kind of index, but rather an infrastructure
-   within which many different indexing strategies can be implemented.
-   Accordingly, the particular operators with which a GiST index can be
-   used vary depending on the indexing strategy (the <firstterm>operator
-   class</firstterm>).  As an example, the standard distribution of
-   <productname>PostgreSQL</productname> includes GiST operator classes
-   for several two-dimensional geometric data types, which support indexed
-   queries using these operators:
+   <para>
+    <indexterm>
+     <primary>index</primary>
+     <secondary>GiST</secondary>
+    </indexterm>
+    <indexterm>
+     <primary>GiST</primary>
+     <see>index</see>
+    </indexterm>
+    GiST indexes are not a single kind of index, but rather an infrastructure
+    within which many different indexing strategies can be implemented.
+    Accordingly, the particular operators with which a GiST index can be
+    used vary depending on the indexing strategy (the <firstterm>operator
+    class</firstterm>).  As an example, the standard distribution of
+    <productname>PostgreSQL</productname> includes GiST operator classes
+    for several two-dimensional geometric data types, which support indexed
+    queries using these operators:
 
 <synopsis>
 <<   &<   &>   >>   <<|   &<|   |&>  
|>>  @>   <@   ~=   &&
 
 </synopsis>
 
-   (See <xref linkend="functions-geometry"/> for the meaning of
-   these operators.)
-   The GiST operator classes included in the standard distribution are
-   documented in <xref linkend="gist-builtin-opclasses-table"/>.
-   Many other GiST operator
-   classes are available in the <literal>contrib</literal> collection or as separate
-   projects.  For more information see <xref linkend="gist"/>.
-  </para>
+    (See <xref linkend="functions-geometry"/> for the meaning of
+    these operators.)
+    The GiST operator classes included in the standard distribution are
+    documented in <xref linkend="gist-builtin-opclasses-table"/>.
+    Many other GiST operator
+    classes are available in the <literal>contrib</literal> collection or as separate
+    projects.  For more information see <xref linkend="gist"/>.
+   </para>
 
-  <para>
-   GiST indexes are also capable of optimizing <quote>nearest-neighbor</quote>
-   searches, such as
+   <para>
+    GiST indexes are also capable of optimizing <quote>nearest-neighbor</quote>
+    searches, such as
 <programlisting><![CDATA[
 SELECT * FROM places ORDER BY location <-> point '(101,456)' LIMIT 10;
 ]]>
 </programlisting>
-   which finds the ten places closest to a given target point.  The ability
-   to do this is again dependent on the particular operator class being used.
-   In <xref linkend="gist-builtin-opclasses-table"/>, operators that can be
-   used in this way are listed in the column <quote>Ordering Operators</quote>.
-  </para>
+    which finds the ten places closest to a given target point.  The ability
+    to do this is again dependent on the particular operator class being used.
+    In <xref linkend="gist-builtin-opclasses-table"/>, operators that can be
+    used in this way are listed in the column <quote>Ordering Operators</quote>.
+   </para>
   </sect2>
 
   <sect2 id="indexes-type-spgist">
    <title>SP-GiST</title>
 
-  <para>
-   <indexterm>
-    <primary>index</primary>
-    <secondary>SP-GiST</secondary>
-   </indexterm>
-   <indexterm>
-    <primary>SP-GiST</primary>
-    <see>index</see>
-   </indexterm>
-   SP-GiST indexes, like GiST indexes, offer an infrastructure that supports
-   various kinds of searches.  SP-GiST permits implementation of a wide range
-   of different non-balanced disk-based data structures, such as quadtrees,
-   k-d trees, and radix trees (tries).  As an example, the standard distribution of
-   <productname>PostgreSQL</productname> includes SP-GiST operator classes
-   for two-dimensional points, which support indexed
-   queries using these operators:
+   <para>
+    <indexterm>
+     <primary>index</primary>
+     <secondary>SP-GiST</secondary>
+    </indexterm>
+    <indexterm>
+     <primary>SP-GiST</primary>
+     <see>index</see>
+    </indexterm>
+    SP-GiST indexes, like GiST indexes, offer an infrastructure that supports
+    various kinds of searches.  SP-GiST permits implementation of a wide range
+    of different non-balanced disk-based data structures, such as quadtrees,
+    k-d trees, and radix trees (tries).  As an example, the standard distribution of
+    <productname>PostgreSQL</productname> includes SP-GiST operator classes
+    for two-dimensional points, which support indexed
+    queries using these operators:
 
 <synopsis>
 <<   >>   ~=   <@   <^   >^
 </synopsis>
 
-   (See <xref linkend="functions-geometry"/> for the meaning of
-   these operators.)
-   The SP-GiST operator classes included in the standard distribution are
-   documented in <xref linkend="spgist-builtin-opclasses-table"/>.
-   For more information see <xref linkend="spgist"/>.
-  </para>
+    (See <xref linkend="functions-geometry"/> for the meaning of
+    these operators.)
+    The SP-GiST operator classes included in the standard distribution are
+    documented in <xref linkend="spgist-builtin-opclasses-table"/>.
+    For more information see <xref linkend="spgist"/>.
+   </para>
 
-  <para>
-   Like GiST, SP-GiST supports <quote>nearest-neighbor</quote> searches.
-   For SP-GiST operator classes that support distance ordering, the
-   corresponding operator is specified in the <quote>Ordering Operators</quote>
-   column in <xref linkend="spgist-builtin-opclasses-table"/>.
-  </para>
+   <para>
+    Like GiST, SP-GiST supports <quote>nearest-neighbor</quote> searches.
+    For SP-GiST operator classes that support distance ordering, the
+    corresponding operator is specified in the <quote>Ordering Operators</quote>
+    column in <xref linkend="spgist-builtin-opclasses-table"/>.
+   </para>
   </sect2>
 
   <sect2 id="indexes-types-gin">
    <title>GIN</title>
 
-  <para>
-   <indexterm>
-    <primary>index</primary>
-    <secondary>GIN</secondary>
-   </indexterm>
-   <indexterm>
-    <primary>GIN</primary>
-    <see>index</see>
-   </indexterm>
-   GIN indexes are <quote>inverted indexes</quote> which are appropriate for
-   data values that contain multiple component values, such as arrays.  An
-   inverted index contains a separate entry for each component value, and
-   can efficiently handle queries that test for the presence of specific
-   component values.
-  </para>
+   <para>
+    <indexterm>
+     <primary>index</primary>
+     <secondary>GIN</secondary>
+    </indexterm>
+    <indexterm>
+     <primary>GIN</primary>
+     <see>index</see>
+    </indexterm>
+    GIN indexes are <quote>inverted indexes</quote> which are appropriate for
+    data values that contain multiple component values, such as arrays.  An
+    inverted index contains a separate entry for each component value, and
+    can efficiently handle queries that test for the presence of specific
+    component values.
+   </para>
 
-  <para>
-   Like GiST and SP-GiST, GIN can support
-   many different user-defined indexing strategies, and the particular
-   operators with which a GIN index can be used vary depending on the
-   indexing strategy.
-   As an example, the standard distribution of
-   <productname>PostgreSQL</productname> includes a GIN operator class
-   for arrays, which supports indexed queries using these operators:
+   <para>
+    Like GiST and SP-GiST, GIN can support
+    many different user-defined indexing strategies, and the particular
+    operators with which a GIN index can be used vary depending on the
+    indexing strategy.
+    As an example, the standard distribution of
+    <productname>PostgreSQL</productname> includes a GIN operator class
+    for arrays, which supports indexed queries using these operators:
 
 <synopsis>
 <@   @>   =   &&
 </synopsis>
 
-   (See <xref linkend="functions-array"/> for the meaning of
-   these operators.)
-   The GIN operator classes included in the standard distribution are
-   documented in <xref linkend="gin-builtin-opclasses-table"/>.
-   Many other GIN operator
-   classes are available in the <literal>contrib</literal> collection or as separate
-   projects.  For more information see <xref linkend="gin"/>.
-  </para>
+    (See <xref linkend="functions-array"/> for the meaning of
+    these operators.)
+    The GIN operator classes included in the standard distribution are
+    documented in <xref linkend="gin-builtin-opclasses-table"/>.
+    Many other GIN operator
+    classes are available in the <literal>contrib</literal> collection or as separate
+    projects.  For more information see <xref linkend="gin"/>.
+   </para>
   </sect2>
 
   <sect2 id="indexes-types-brin">
    <title>BRIN</title>
 
-  <para>
-   <indexterm>
-    <primary>index</primary>
-    <secondary>BRIN</secondary>
-   </indexterm>
-   <indexterm>
-    <primary>BRIN</primary>
-    <see>index</see>
-   </indexterm>
-   BRIN indexes (a shorthand for Block Range INdexes) store summaries about
-   the values stored in consecutive physical block ranges of a table.
-   Like GiST, SP-GiST and GIN,
-   BRIN can support many different indexing strategies,
-   and the particular operators with which a BRIN index can be used
-   vary depending on the indexing strategy.
-   For data types that have a linear sort order, the indexed data
-   corresponds to the minimum and maximum values of the
-   values in the column for each block range.  This supports indexed queries
-   using these operators:
+   <para>
+    <indexterm>
+     <primary>index</primary>
+     <secondary>BRIN</secondary>
+    </indexterm>
+    <indexterm>
+     <primary>BRIN</primary>
+     <see>index</see>
+    </indexterm>
+    BRIN indexes (a shorthand for Block Range INdexes) store summaries about
+    the values stored in consecutive physical block ranges of a table.
+    Like GiST, SP-GiST and GIN,
+    BRIN can support many different indexing strategies,
+    and the particular operators with which a BRIN index can be used
+    vary depending on the indexing strategy.
+    For data types that have a linear sort order, the indexed data
+    corresponds to the minimum and maximum values of the
+    values in the column for each block range.  This supports indexed queries
+    using these operators:
 
 <synopsis>
 <   <=   =   >=   >
 </synopsis>
 
-   The BRIN operator classes included in the standard distribution are
-   documented in <xref linkend="brin-builtin-opclasses-table"/>.
-   For more information see <xref linkend="brin"/>.
-  </para>
+    The BRIN operator classes included in the standard distribution are
+    documented in <xref linkend="brin-builtin-opclasses-table"/>.
+    For more information see <xref linkend="brin"/>.
+   </para>
   </sect2>
  </sect1>
 
-- 
2.27.0