Add some more documentation and cross-links on using dblink with SQL/MED.

diff --git a/doc/src/sgml/dblink.sgml b/doc/src/sgml/dblink.sgml
index 06fcc8cee8bfd7c32de384864e876db45490b0a9..2afa40a29f6efaba8ad7486652c7f3a9e19957a4 100644 (file)
--- a/doc/src/sgml/dblink.sgml
+++ b/doc/src/sgml/dblink.sgml
@@ -1,4 +1,4 @@
-
+
 
 
  dblink
@@ -45,8 +45,10 @@
 
    
     The connection string may also be the name of an existing foreign
-    server that utilizes the postgresql_fdw foreign data wrapper library.
-    See the example below, as well as the following:
+    server.  It is recommended to use
+    the postgresql_fdw_validator when defining
+    the corresponding foreign-data wrapper.  See the example below, as
+    well as the following:
     
      
      
@@ -134,7 +136,7 @@
  --       DETAIL:  Non-superuser cannot connect if the server does not request a password.
  --       HINT:  Target server's authentication method must be changed.
  CREATE USER dblink_regression_test WITH PASSWORD 'secret';
- CREATE FOREIGN DATA WRAPPER postgresql;
+ CREATE FOREIGN DATA WRAPPER postgresql VALIDATOR postgresql_fdw_validator;
  CREATE SERVER fdtest FOREIGN DATA WRAPPER postgresql OPTIONS (hostaddr '127.0.0.1', dbname 'contrib_regression');
 
  CREATE USER MAPPING FOR dblink_regression_test SERVER fdtest OPTIONS (user 'dblink_regression_test', password 'secret');

diff --git a/doc/src/sgml/ref/create_foreign_data_wrapper.sgml b/doc/src/sgml/ref/create_foreign_data_wrapper.sgml
index bc615476bdc14d63b56a26fe3e72d08fb821464e..dd48245372d18dc79f13b6e257a0dd7fc2635cf1 100644 (file)
--- a/doc/src/sgml/ref/create_foreign_data_wrapper.sgml
+++ b/doc/src/sgml/ref/create_foreign_data_wrapper.sgml
@@ -1,5 +1,5 @@
 
 
@@ -103,7 +103,9 @@ CREATE FOREIGN DATA WRAPPER name
    rudimentary.  The purpose of foreign-data wrappers, foreign
    servers, and user mappings is to store this information in a
    standard way so that it can be queried by interested applications.
-   The functionality to actually query external data does not exist
+   One such application is dblink;
+   see .  The functionality to actually query
+   external data through a foreign-data wrapper library does not exist
    yet.
   
 

diff --git a/doc/src/sgml/ref/create_server.sgml b/doc/src/sgml/ref/create_server.sgml
index c588e6b3e6ab4aeed1118600afdcd3f1cb511cab..c828c5a28b62b5318ad3088ee241a58e93cb9f71 100644 (file)
--- a/doc/src/sgml/ref/create_server.sgml
+++ b/doc/src/sgml/ref/create_server.sgml
@@ -1,5 +1,5 @@
 
 
@@ -34,6 +34,13 @@ CREATE SERVER servername [ TYPE 'se
    user who defines the server becomes its owner.
   
 
+  
+   A foreign server typically encapsulates connection information that
+   a foreign-data wrapper uses to access an external data resource.
+   Additional user-specific connection information may be specified by
+   means of user mappings.
+  
+
   
    The server name must be unique within the database.
   
@@ -98,6 +105,20 @@ CREATE SERVER servername [ TYPE 'se
   
  
 
+ 
+  Notes
+
+  
+   When using the dblink module
+   (see ), the foreign server name can be used
+   as an argument of the 
+   function to indicate the connection parameters.  See also there for
+   more examples.  It is necessary to have
+   the USAGE privilege on the foreign server to be
+   able to use it in this way.
+  
+ 
+
  
   Examples
 

diff --git a/doc/src/sgml/ref/create_user_mapping.sgml b/doc/src/sgml/ref/create_user_mapping.sgml
index 6d40eaf936b76cabebcb7abe73fdf64974692e47..ab7ff7fdb10717f43be6b08b391bae804bfa0920 100644 (file)
--- a/doc/src/sgml/ref/create_user_mapping.sgml
+++ b/doc/src/sgml/ref/create_user_mapping.sgml
@@ -1,5 +1,5 @@
 
 
@@ -31,7 +31,10 @@ CREATE USER MAPPING FOR { username
 
   
    CREATE USER MAPPING defines a mapping of a user
-   to a foreign server.
+   to a foreign server.  A user mapping typically encapsulates
+   connection information that a foreign-data wrapper uses together
+   with the information encapsulated be a foreign server to access an
+   external data resource.
   
 
   
@@ -52,8 +55,9 @@ CREATE USER MAPPING FOR { username
      
       The name of an existing user that is mapped to foreign server.
       CURRENT_USER and USER match the name of
-      the current user.  PUBLIC is used to match all
-      present and future user names in the system.
+      the current user.  When PUBLIC is specified, a
+      so-called public mapping is created that is used when no
+      user-specific mapping is applicable.