doc: Small improvement in CREATE TABLE / PERIOD documentation

Use placeholders that are more consistent and match the description
better.  Fixup for commit 89f908a6d0a.

diff --git a/doc/src/sgml/ref/create_table.sgml b/doc/src/sgml/ref/create_table.sgml
index dd83b07d65f0d3b46ca3ab174908b3de1c815cc8..6262533c57ba25c62502b58c6cff46dab45122e9 100644 (file)
--- a/doc/src/sgml/ref/create_table.sgml
+++ b/doc/src/sgml/ref/create_table.sgml
@@ -81,7 +81,7 @@ CREATE [ [ GLOBAL | LOCAL ] { TEMPORARY | TEMP } | UNLOGGED ] TABLE [ IF NOT EXI
   UNIQUE [ NULLS [ NOT ] DISTINCT ] ( column_name [, ... ] [, column_name WITHOUT OVERLAPS ] ) index_parameters |
   PRIMARY KEY ( column_name [, ... ] [, column_name WITHOUT OVERLAPS ] ) index_parameters |
   EXCLUDE [ USING index_method ] ( exclude_element WITH operator [, ... ] ) index_parameters [ WHERE ( predicate ) ] |
-  FOREIGN KEY ( column_name [, ... ] [, PERIOD column_name ] ) REFERENCES reftable [ ( refcolumn [, ... ] [, PERIOD column_name ] ) ]
+  FOREIGN KEY ( column_name [, ... ] [, PERIOD column_name ] ) REFERENCES reftable [ ( refcolumn [, ... ] [, PERIOD refcolumn ] ) ]
     [ MATCH FULL | MATCH PARTIAL | MATCH SIMPLE ] [ ON DELETE 
 class="parameter">referential_action ] [ ON UPDATE referential_action ] }
 [ DEFERRABLE | NOT DEFERRABLE ] [ INITIALLY DEFERRED | INITIALLY IMMEDIATE ]
@@ -1165,7 +1165,7 @@ WITH ( MODULUS numeric_literal, REM
     REFERENCES reftable [ ( refcolumn ) ] [ MATCH matchtype ] [ ON DELETE referential_action ] [ ON UPDATE referential_action ] (column constraint)
 
    FOREIGN KEY ( column_name [, ... ] [, PERIOD column_name ] )
-    REFERENCES reftable [ ( refcolumn [, ... ] [, PERIOD column_name ] ) ]
+    REFERENCES reftable [ ( refcolumn [, ... ] [, PERIOD refcolumn ] ) ]
     [ MATCH matchtype ]
     [ ON DELETE referential_action ]
     [ ON UPDATE referential_action ]