3 files changed, 10 insertions, 13 deletions
diff --git a/doc/src/sgml/catalogs.sgml b/doc/src/sgml/catalogs.sgml
index 23b570d883..5240840552 100644
--- a/doc/src/sgml/catalogs.sgml
+++ b/doc/src/sgml/catalogs.sgml
@@ -2552,7 +2552,6 @@ SCRAM-SHA-256$<replaceable>&lt;iteration count&gt;</replaceable>:<replaceable>&l
       <para>
        <literal>c</literal> = check constraint,
        <literal>f</literal> = foreign key constraint,
-       <literal>n</literal> = not null constraint,
        <literal>p</literal> = primary key constraint,
        <literal>u</literal> = unique constraint,
        <literal>t</literal> = constraint trigger,
diff --git a/doc/src/sgml/ref/alter_table.sgml b/doc/src/sgml/ref/alter_table.sgml
index 0b65731b1f..d4d93eeb7c 100644
--- a/doc/src/sgml/ref/alter_table.sgml
+++ b/doc/src/sgml/ref/alter_table.sgml
@@ -117,9 +117,7 @@ WITH ( MODULUS <replaceable class="parameter">numeric_literal</replaceable>, REM
   PRIMARY KEY ( <replaceable class="parameter">column_name</replaceable> [, ... ] ) <replaceable class="parameter">index_parameters</replaceable> |
   EXCLUDE [ USING <replaceable class="parameter">index_method</replaceable> ] ( <replaceable class="parameter">exclude_element</replaceable> WITH <replaceable class="parameter">operator</replaceable> [, ... ] ) <replaceable class="parameter">index_parameters</replaceable> [ WHERE ( <replaceable class="parameter">predicate</replaceable> ) ] |
   FOREIGN KEY ( <replaceable class="parameter">column_name</replaceable> [, ... ] ) REFERENCES <replaceable class="parameter">reftable</replaceable> [ ( <replaceable class="parameter">refcolumn</replaceable> [, ... ] ) ]
-    [ MATCH FULL | MATCH PARTIAL | MATCH SIMPLE ] [ ON DELETE <replaceable class="parameter">referential_action</replaceable> ] [ ON UPDATE <replaceable class="parameter">referential_action</replaceable> ] |
-  NOT NULL <replaceable class="parameter">column_name</replaceable> [ NO INHERIT ]
-}
+    [ MATCH FULL | MATCH PARTIAL | MATCH SIMPLE ] [ ON DELETE <replaceable class="parameter">referential_action</replaceable> ] [ ON UPDATE <replaceable class="parameter">referential_action</replaceable> ] }
 [ DEFERRABLE | NOT DEFERRABLE ] [ INITIALLY DEFERRED | INITIALLY IMMEDIATE ]
 
 <phrase>and <replaceable class="parameter">table_constraint_using_index</replaceable> is:</phrase>
@@ -1765,17 +1763,11 @@ ALTER TABLE measurement
   <title>Compatibility</title>
 
   <para>
-   The forms <literal>ADD COLUMN</literal>
+   The forms <literal>ADD</literal> (without <literal>USING INDEX</literal>),
    <literal>DROP [COLUMN]</literal>, <literal>DROP IDENTITY</literal>, <literal>RESTART</literal>,
    <literal>SET DEFAULT</literal>, <literal>SET DATA TYPE</literal> (without <literal>USING</literal>),
    <literal>SET GENERATED</literal>, and <literal>SET <replaceable>sequence_option</replaceable></literal>
-   conform with the SQL standard.
-   The form <literal>ADD <replaceable>table_constraint</replaceable></literal>
-   conforms with the SQL standard when the <literal>USING INDEX</literal> and
-   <literal>NOT VALID</literal> clauses are omitted and the constraint type is
-   one of <literal>UNIQUE</literal>, <literal>PRIMARY KEY</literal>
-   or <literal>REFERENCES</literal>.
-   The other forms are
+   conform with the SQL standard.  The other forms are
    <productname>PostgreSQL</productname> extensions of the SQL standard.
    Also, the ability to specify more than one manipulation in a single
    <command>ALTER TABLE</command> command is an extension.
diff --git a/doc/src/sgml/ref/create_table.sgml b/doc/src/sgml/ref/create_table.sgml
index 22fdd8bac2..10ef699fab 100644
--- a/doc/src/sgml/ref/create_table.sgml
+++ b/doc/src/sgml/ref/create_table.sgml
@@ -77,7 +77,6 @@ CREATE [ [ GLOBAL | LOCAL ] { TEMPORARY | TEMP } | UNLOGGED ] TABLE [ IF NOT EXI
 
 [ CONSTRAINT <replaceable class="parameter">constraint_name</replaceable> ]
 { CHECK ( <replaceable class="parameter">expression</replaceable> ) [ NO INHERIT ] |
-  NOT NULL <replaceable class="parameter">column_name</replaceable> |
   UNIQUE [ NULLS [ NOT ] DISTINCT ] ( <replaceable class="parameter">column_name</replaceable> [, ... ] ) <replaceable class="parameter">index_parameters</replaceable> |
   PRIMARY KEY ( <replaceable class="parameter">column_name</replaceable> [, ... ] ) <replaceable class="parameter">index_parameters</replaceable> |
   EXCLUDE [ USING <replaceable class="parameter">index_method</replaceable> ] ( <replaceable class="parameter">exclude_element</replaceable> WITH <replaceable class="parameter">operator</replaceable> [, ... ] ) <replaceable class="parameter">index_parameters</replaceable> [ WHERE ( <replaceable class="parameter">predicate</replaceable> ) ] |
@@ -2315,6 +2314,13 @@ CREATE TABLE cities_partdef
     constraint, and index names must be unique across all relations within
     the same schema.
    </para>
+
+   <para>
+    Currently, <productname>PostgreSQL</productname> does not record names
+    for <literal>NOT NULL</literal> constraints at all, so they are not
+    subject to the uniqueness restriction.  This might change in a future
+    release.
+   </para>
   </refsect2>
 
   <refsect2>