diff --git a/doc/src/sgml/nullvalues.sgml b/doc/src/sgml/nullvalues.sgml
index 6c7aaed37a..1a9e698a55 100644
--- a/doc/src/sgml/nullvalues.sgml
+++ b/doc/src/sgml/nullvalues.sgml
@@ -12,14 +12,14 @@
   can be executed so long as the following table and rows are created first.
  </para>
 
- <programlisting>
-  CREATE TABLE null_examples (
-    id bigint PRIMARY KEY,
-    value integer NULL
-  );
-  INSERT INTO null_examples
-  VALUES (1, 1), (2, NULL), (3, 4);
- </programlisting>
+<programlisting>
+CREATE TABLE null_examples (
+  id bigint PRIMARY KEY,
+  value integer NULL
+);
+INSERT INTO null_examples
+VALUES (1, 1), (2, NULL), (3, 4);
+</programlisting>
 
  <sect2 id="nullvalues-model">
   <title>Meaning</title>
@@ -38,7 +38,7 @@
    A null value, like all values, must have a data type, and is valid for all data types.
   </para>
   <para>
-   As noted in the <link linkend="sql-syntax-constants-nullvalue">synatx chapter</link>,
+   As noted in the <link linkend="sql-syntax-constants-nullvalue">syntax chapter</link>,
    a null value literal is written using the <literal>NULL</literal> keyword.
    Its type is the <link linkend="datatype-pseudo">pseudo-type unknown</link>
    but can be cast to any concrete data type.
@@ -60,11 +60,11 @@
   </para>
   <para>
 <programlisting>
- SELECT text NULL;
+SELECT text NULL;
 </programlisting>
 <screen>
- ERROR:  column "text" does not exist
- LINE 1: select text NUll;
+ERROR:  column "text" does not exist
+LINE 1: select text NUll;
 </screen>
   </para>
   <para>
@@ -267,28 +267,28 @@
    the value will be null.  The common way this happens is by including the domain column's table
    on the right side of a left join.
 <programlisting>
- BEGIN;
- CREATE DOMAIN domain_example AS integer NOT NULL;
- CREATE TABLE domain_examples (de_id bigint PRIMARY KEY, de_value domain_example);
- INSERT INTO domain_examples VALUES (1, 1), (2, 2);
- SELECT *, pg_typeof(de_value)
- FROM null_examples AS ne
- LEFT JOIN domain_examples AS de ON ne.id = de.de_id;
- ROLLBACK;
-</programlisting>
-<screen>
- BEGIN
- CREATE DOMAIN
- CREATE TABLE
- INSERT 0 2
-  id | value | de_id | de_value |   pg_typeof
- ----+-------+-------+----------+----------------
-   1 |     1 |     1 |        1 | domain_example
-   2 |       |     2 |        2 | domain_example
-   3 |     4 |       |          | domain_example
- (3 rows)
-
- ROLLBACK
+BEGIN;
+CREATE DOMAIN domain_example AS integer NOT NULL;
+CREATE TABLE domain_examples (de_id bigint PRIMARY KEY, de_value domain_example);
+INSERT INTO domain_examples VALUES (1, 1), (2, 2);
+SELECT *, pg_typeof(de_value)
+FROM null_examples AS ne
+LEFT JOIN domain_examples AS de ON ne.id = de.de_id;
+ROLLBACK;
+</programlisting>
+<screen>
+BEGIN
+CREATE DOMAIN
+CREATE TABLE
+INSERT 0 2
+ id | value | de_id | de_value |   pg_typeof
+----+-------+-------+----------+----------------
+  1 |     1 |     1 |        1 | domain_example
+  2 |       |     2 |        2 | domain_example
+  3 |     4 |       |          | domain_example
+(3 rows)
+
+ROLLBACK
 </screen>
    Please see the details in the <link linkend="sql-createdomain-notes">
    notes on the create domain page</link> for another example, as well as
@@ -698,24 +698,24 @@
    when an expression evaulates to a null value, is to allow the row to be inserted
    - the same as a true result.
 <programlisting>
- BEGIN;
- ALTER TABLE null_examples ADD CONSTRAINT value_not_1 CHECK (value != 1);
- ROLLBACK;
+BEGIN;
+ALTER TABLE null_examples ADD CONSTRAINT value_not_1 CHECK (value != 1);
+ROLLBACK;
 </programlisting>
 <screen>
- BEGIN
- ERROR:  check constraint "value_not_1" of relation "null_examples" is violated by some row
- ROLLBACK
+BEGIN
+ERROR:  check constraint "value_not_1" of relation "null_examples" is violated by some row
+ROLLBACK
 </screen>
 <programlisting>
- BEGIN;
- ALTER TABLE null_examples ADD CONSTRAINT value_not_10 CHECK (value != 10);
- ROLLBACK;
+BEGIN;
+ALTER TABLE null_examples ADD CONSTRAINT value_not_10 CHECK (value != 10);
+ROLLBACK;
 </programlisting>
 <screen>
- BEGIN
- ALTER TABLE
- ROLLBACK
+BEGIN
+ALTER TABLE
+ROLLBACK
 </screen>
    We are using a transaction (begin and rollback) and the alter table command to add two
    constraints to our null_examples table.  The first constraint prohibits rows with a value
@@ -817,31 +817,31 @@
   </para>
   <para>
 <programlisting>
- BEGIN;
- CREATE UNIQUE INDEX value_nulls_distinct_implicit ON null_examples (value);
- CREATE UNIQUE INDEX value_nulls_distinct_explicit ON null_examples (value) NULLS DISTINCT;
- INSERT INTO null_examples VALUES (4, NULL);
- ROLLBACK;
+BEGIN;
+CREATE UNIQUE INDEX value_nulls_distinct_implicit ON null_examples (value);
+CREATE UNIQUE INDEX value_nulls_distinct_explicit ON null_examples (value) NULLS DISTINCT;
+INSERT INTO null_examples VALUES (4, NULL);
+ROLLBACK;
 </programlisting>
 <screen>
- BEGIN
- CREATE INDEX
- CREATE INDEX
- INSERT 0 1
- ROLLBACK
+BEGIN
+CREATE INDEX
+CREATE INDEX
+INSERT 0 1
+ROLLBACK
 </screen>
 <programlisting>
- BEGIN;
- CREATE UNIQUE INDEX value_nulls_not_distinct_explicit ON null_examples (value) NULLS NOT DISTINCT;
- INSERT INTO null_examples VALUES (4, NULL);
- ROLLBACK;
+BEGIN;
+CREATE UNIQUE INDEX value_nulls_not_distinct_explicit ON null_examples (value) NULLS NOT DISTINCT;
+INSERT INTO null_examples VALUES (4, NULL);
+ROLLBACK;
 </programlisting>
 <screen>
- BEGIN
- CREATE INDEX
- ERROR:  duplicate key value violates unique constraint "value_nulls_not_distinct_explicit"
- DETAIL:  Key (value)=(null) already exists.
- ROLLBACK
+BEGIN
+CREATE INDEX
+ERROR:  duplicate key value violates unique constraint "value_nulls_not_distinct_explicit"
+DETAIL:  Key (value)=(null) already exists.
+ROLLBACK
 </screen>
   </para>
   <para>
@@ -859,7 +859,7 @@
  </sect2>
 
  <sect2 id="nullvalues-partitionkeys">
-  <title>Null Values in Partiton Keys</title>
+  <title>Null Values in Partition Keys</title>
   <para>
    At present this is typically a non-issue as <productname>PostgreSQL</productname>
    does not support a primary key that does not include partition key columns, and
@@ -876,7 +876,7 @@
  <sect2 id="nullvalues-settings">
   <title>Null-Valued Settings</title>
   <para>
-   There are none.  During initializion all settings are assigned a non-null value.
+   There are none. During initialization all settings are assigned a non-null value.
   </para>
   <para>
    This is mostly meaningful for <link linkend="runtime-config-custom">custom settings</link>,