docs: consistently uppercase index method and add spacing

Consistently uppercase index method names, e.g. GIN, and add space after
the index method name and the parentheses enclosing the column names.

doc/src/sgml/btree-gin.sgml

@@ -36,7 +36,7 @@
 <programlisting>
 CREATE TABLE test (a int4);
 -- create index
-CREATE INDEX testidx ON test USING gin (a);
+CREATE INDEX testidx ON test USING GIN (a);
 -- query
 SELECT * FROM test WHERE a &lt; 10;
 </programlisting>

doc/src/sgml/btree-gist.sgml

@@ -61,7 +61,7 @@
 <programlisting>
 CREATE TABLE test (a int4);
 -- create index
-CREATE INDEX testidx ON test USING gist (a);
+CREATE INDEX testidx ON test USING GIST (a);
 -- query
 SELECT * FROM test WHERE a &lt; 10;
 -- nearest-neighbor search: find the ten entries closest to "42"
@@ -78,7 +78,7 @@ SELECT *, a &lt;-&gt; 42 AS dist FROM test ORDER BY a &lt;-&gt; 42 LIMIT 10;
 =&gt; CREATE TABLE zoo (
   cage   INTEGER,
   animal TEXT,
-  EXCLUDE USING gist (cage WITH =, animal WITH &lt;&gt;)
+  EXCLUDE USING GIST (cage WITH =, animal WITH &lt;&gt;)
 );
 
 =&gt; INSERT INTO zoo VALUES(123, 'zebra');

doc/src/sgml/gist.sgml

@@ -220,7 +220,7 @@
   To use it, mention the class name in <command>CREATE INDEX</>,
   for example
 <programlisting>
-CREATE INDEX ON my_table USING gist (my_inet_column inet_ops);
+CREATE INDEX ON my_table USING GIST (my_inet_column inet_ops);
 </programlisting>
  </para>
 

doc/src/sgml/indices.sgml

@@ -189,7 +189,7 @@ CREATE INDEX test1_id_index ON test1 (id);
    <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>);
+CREATE INDEX <replaceable>name</replaceable> ON <replaceable>table</replaceable> USING HASH (<replaceable>column</replaceable>);
 </synopsis>
   </para>
 

doc/src/sgml/json.sgml

@@ -375,13 +375,13 @@ SELECT '"foo"'::jsonb ? 'foo';
     implement, see <xref linkend="functions-jsonb-op-table">.)
     An example of creating an index with this operator class is:
 <programlisting>
-CREATE INDEX idxgin ON api USING gin (jdoc);
+CREATE INDEX idxgin ON api USING GIN (jdoc);
 </programlisting>
     The non-default GIN operator class <literal>jsonb_path_ops</>
     supports indexing the <literal>@&gt;</> operator only.
     An example of creating an index with this operator class is:
 <programlisting>
-CREATE INDEX idxginp ON api USING gin (jdoc jsonb_path_ops);
+CREATE INDEX idxginp ON api USING GIN (jdoc jsonb_path_ops);
 </programlisting>
   </para>
 
@@ -426,7 +426,7 @@ SELECT jdoc-&gt;'guid', jdoc-&gt;'name' FROM api WHERE jdoc -&gt; 'tags' ? 'qui'
     the <literal>"tags"</> key is common, defining an index like this
     may be worthwhile:
 <programlisting>
-CREATE INDEX idxgintags ON api USING gin ((jdoc -&gt; 'tags'));
+CREATE INDEX idxgintags ON api USING GIN ((jdoc -&gt; 'tags'));
 </programlisting>
     Now, the <literal>WHERE</> clause <literal>jdoc -&gt; 'tags' ? 'qui'</>
     will be recognized as an application of the indexable

doc/src/sgml/ltree.sgml

@@ -550,8 +550,8 @@ INSERT INTO test VALUES ('Top.Collections.Pictures.Astronomy');
 INSERT INTO test VALUES ('Top.Collections.Pictures.Astronomy.Stars');
 INSERT INTO test VALUES ('Top.Collections.Pictures.Astronomy.Galaxies');
 INSERT INTO test VALUES ('Top.Collections.Pictures.Astronomy.Astronauts');
-CREATE INDEX path_gist_idx ON test USING gist(path);
-CREATE INDEX path_idx ON test USING btree(path);
+CREATE INDEX path_gist_idx ON test USING GIST (path);
+CREATE INDEX path_idx ON test USING BTREE (path);
 </programlisting>
 
   <para>

doc/src/sgml/pgtrgm.sgml

@@ -168,11 +168,11 @@
 
 <programlisting>
 CREATE TABLE test_trgm (t text);
-CREATE INDEX trgm_idx ON test_trgm USING gist (t gist_trgm_ops);
+CREATE INDEX trgm_idx ON test_trgm USING GIST (t gist_trgm_ops);
 </programlisting>
 or
 <programlisting>
-CREATE INDEX trgm_idx ON test_trgm USING gin (t gin_trgm_ops);
+CREATE INDEX trgm_idx ON test_trgm USING GIN (t gin_trgm_ops);
 </programlisting>
   </para>
 
@@ -274,7 +274,7 @@ CREATE TABLE words AS SELECT word FROM
    Next, create a trigram index on the word column:
 
 <programlisting>
-CREATE INDEX words_idx ON words USING gin(word gin_trgm_ops);
+CREATE INDEX words_idx ON words USING GIN (word gin_trgm_ops);
 </programlisting>
 
    Now, a <command>SELECT</command> query similar to the previous example can

doc/src/sgml/rangetypes.sgml

@@ -406,7 +406,7 @@ SELECT '[1.234, 5.678]'::floatrange;
    GiST and SP-GiST indexes can be created for table columns of range types.
    For instance, to create a GiST index:
 <programlisting>
-CREATE INDEX reservation_idx ON reservation USING gist (during);
+CREATE INDEX reservation_idx ON reservation USING GIST (during);
 </programlisting>
    A GiST or SP-GiST index can accelerate queries involving these range operators:
    <literal>=</>,
@@ -453,7 +453,7 @@ CREATE INDEX reservation_idx ON reservation USING gist (during);
 <programlisting>
 CREATE TABLE reservation (
     during tsrange,
-    EXCLUDE USING gist (during WITH &amp;&amp;)
+    EXCLUDE USING GIST (during WITH &amp;&amp;)
 );
 </programlisting>
 
@@ -486,7 +486,7 @@ CREATE EXTENSION btree_gist;
 CREATE TABLE room_reservation (
     room text,
     during tsrange,
-    EXCLUDE USING gist (room WITH =, during WITH &amp;&amp;)
+    EXCLUDE USING GIST (room WITH =, during WITH &amp;&amp;)
 );
 
 INSERT INTO room_reservation VALUES

doc/src/sgml/ref/create_index.sgml

@@ -637,7 +637,7 @@ CREATE UNIQUE INDEX title_idx ON films (title) WITH (fillfactor = 70);
   <para>
    To create a <acronym>GIN</> index with fast updates disabled:
 <programlisting>
-CREATE INDEX gin_idx ON documents_table USING gin (locations) WITH (fastupdate = off);
+CREATE INDEX gin_idx ON documents_table USING GIN (locations) WITH (fastupdate = off);
 </programlisting>
   </para>
 

doc/src/sgml/textsearch.sgml

@@ -481,7 +481,7 @@ LIMIT 10;
     linkend="textsearch-indexes">) to speed up text searches:
 
 <programlisting>
-CREATE INDEX pgweb_idx ON pgweb USING gin(to_tsvector('english', body));
+CREATE INDEX pgweb_idx ON pgweb USING GIN (to_tsvector('english', body));
 </programlisting>
 
     Notice that the 2-argument version of <function>to_tsvector</function> is
@@ -511,7 +511,7 @@ CREATE INDEX pgweb_idx ON pgweb USING gin(to_tsvector('english', body));
     configuration name is specified by another column, e.g.:
 
 <programlisting>
-CREATE INDEX pgweb_idx ON pgweb USING gin(to_tsvector(config_name, body));
+CREATE INDEX pgweb_idx ON pgweb USING GIN (to_tsvector(config_name, body));
 </programlisting>
 
     where <literal>config_name</> is a column in the <literal>pgweb</>
@@ -527,7 +527,7 @@ CREATE INDEX pgweb_idx ON pgweb USING gin(to_tsvector(config_name, body));
     Indexes can even concatenate columns:
 
 <programlisting>
-CREATE INDEX pgweb_idx ON pgweb USING gin(to_tsvector('english', title || ' ' || body));
+CREATE INDEX pgweb_idx ON pgweb USING GIN (to_tsvector('english', title || ' ' || body));
 </programlisting>
    </para>
 
@@ -547,7 +547,7 @@ UPDATE pgweb SET textsearchable_index_col =
     Then we create a <acronym>GIN</acronym> index to speed up the search:
 
 <programlisting>
-CREATE INDEX textsearch_idx ON pgweb USING gin(textsearchable_index_col);
+CREATE INDEX textsearch_idx ON pgweb USING GIN (textsearchable_index_col);
 </programlisting>
 
     Now we are ready to perform a fast full text search:
@@ -3217,7 +3217,7 @@ SELECT plainto_tsquery('supernovae stars');
       <tertiary>text search</tertiary>
      </indexterm>
 
-      <literal>CREATE INDEX <replaceable>name</replaceable> ON <replaceable>table</replaceable> USING gist(<replaceable>column</replaceable>);</literal>
+      <literal>CREATE INDEX <replaceable>name</replaceable> ON <replaceable>table</replaceable> USING GIST (<replaceable>column</replaceable>);</literal>
      </term>
 
      <listitem>
@@ -3238,7 +3238,7 @@ SELECT plainto_tsquery('supernovae stars');
       <tertiary>text search</tertiary>
      </indexterm>
 
-      <literal>CREATE INDEX <replaceable>name</replaceable> ON <replaceable>table</replaceable> USING gin(<replaceable>column</replaceable>);</literal>
+      <literal>CREATE INDEX <replaceable>name</replaceable> ON <replaceable>table</replaceable> USING GIN (<replaceable>column</replaceable>);</literal>
      </term>
 
      <listitem>