Mapping schemas and databases to XML and XML Schema.

Refactor and document the remaining mapping code.

doc/src/sgml/func.sgml

-<!-- $PostgreSQL: pgsql/doc/src/sgml/func.sgml,v 1.371 2007/03/25 11:56:01 ishii Exp $ -->
+<!-- $PostgreSQL: pgsql/doc/src/sgml/func.sgml,v 1.372 2007/04/01 09:00:24 petere Exp $ -->
 
  <chapter id="functions">
   <title>Functions and Operators</title>
@@ -11427,7 +11427,7 @@ cursor_to_xml(cursor refcursor, count int, nulls boolean, tableforest boolean, t
     query whose text is passed as parameter
     <parameter>query</parameter> and maps the result set.
     <function>cursor_to_xml</function> fetches the indicated number of
-    rows from the cursor specificed by the parameter
+    rows from the cursor specified by the parameter
     <parameter>cursor</parameter>.  This variant is recommendable if
     large tables have to be mapped, because the result value is built
     up in memory by each function.
@@ -11492,7 +11492,7 @@ cursor_to_xml(cursor refcursor, count int, nulls boolean, tableforest boolean, t
     values should be included in the output.  If true, null values in
     columns are represented as
 <screen><![CDATA[
-<columname xsi:nil="true"/>
+<columnname xsi:nil="true"/>
 ]]></screen>
     where <literal>xsi</literal> is the XML namespace prefix for XML
     Schema Instance.  An appropriate namespace declaration will be
@@ -11530,6 +11530,65 @@ query_to_xml_and_xmlschema(query text, nulls boolean, tableforest boolean, targe
 </synopsis>
    </para>
 
+   <para>
+    In addition, the following functions are available to produce
+    analogous mappings of entire schemas or the entire current
+    database.
+<synopsis>
+schema_to_xml(schema name, nulls boolean, tableforest boolean, targetns text)
+schema_to_xmlschema(schema name, nulls boolean, tableforest boolean, targetns text)
+schema_to_xml_and_xmlschema(schema name, nulls boolean, tableforest boolean, targetns text)
+
+database_to_xml(nulls boolean, tableforest boolean, targetns text)
+database_to_xmlschema(nulls boolean, tableforest boolean, targetns text)
+database_to_xml_and_xmlschema(nulls boolean, tableforest boolean, targetns text)
+</synopsis>
+
+    Note that these potentially produce a lot of data, which needs to
+    be built up in memory.  When requesting content mappings of large
+    schemas or databases, it may be worthwhile to consider mapping the
+    tables separately instead, possibly even through a cursor.
+   </para>
+
+   <para>
+    The result of a schema content mapping looks like this:
+
+<screen><![CDATA[
+<schemaname>
+
+table1-mapping
+
+table2-mapping
+
+...
+
+</schemaname>]]></screen>
+
+    where the format of a table mapping depends on the
+    <parameter>tableforest</parameter> parameter as explained above.
+   </para>
+
+   <para>
+    The result of a database content mapping looks like this:
+
+<screen><![CDATA[
+<dbname>
+
+<schema1name>
+  ...
+</schema1name>
+
+<schema2name>
+  ...
+</schema2name>
+
+...
+
+</dbname>]]></screen>
+
+    where the schema mapping is as above.
+   </para>
+
    <para>
     As an example for using the output produced by these functions,
     <xref linkend="xslt-xml-html"> shows an XSLT stylesheet that

src/include/catalog/pg_proc.h

@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2007, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/catalog/pg_proc.h,v 1.452 2007/03/30 18:34:56 mha Exp $
+ * $PostgreSQL: pgsql/src/include/catalog/pg_proc.h,v 1.453 2007/04/01 09:00:25 petere Exp $
  *
  * NOTES
  *	  The script catalog/genbki.sh reads this file and generates .bki
@@ -4100,6 +4100,20 @@ DESCR("map table contents and structure to XML and XML Schema");
 DATA(insert OID = 2930 (  query_to_xml_and_xmlschema  PGNSP PGUID 12 100 0 f f t f s 4 142 "25 16 16 25" _null_ _null_ "{query,nulls,tableforest,targetns}" query_to_xml_and_xmlschema - _null_ ));
 DESCR("map query result and structure to XML and XML Schema");
 
+DATA(insert OID = 2933 (  schema_to_xml               PGNSP PGUID 12 100 0 f f t f s 4 142 "19 16 16 25" _null_ _null_ "{schema,nulls,tableforest,targetns}" schema_to_xml - _null_ ));
+DESCR("map schema contents to XML");
+DATA(insert OID = 2934 (  schema_to_xmlschema         PGNSP PGUID 12 100 0 f f t f s 4 142 "19 16 16 25" _null_ _null_ "{schema,nulls,tableforest,targetns}" schema_to_xmlschema - _null_ ));
+DESCR("map schema structure to XML Schema");
+DATA(insert OID = 2935 (  schema_to_xml_and_xmlschema PGNSP PGUID 12 100 0 f f t f s 4 142 "19 16 16 25" _null_ _null_ "{schema,nulls,tableforest,targetns}" schema_to_xml_and_xmlschema - _null_ ));
+DESCR("map schema contents and structure to XML and XML Schema");
+
+DATA(insert OID = 2936 (  database_to_xml             PGNSP PGUID 12 100 0 f f t f s 3 142 "16 16 25" _null_ _null_ "{nulls,tableforest,targetns}" database_to_xml - _null_ ));
+DESCR("map database contents to XML");
+DATA(insert OID = 2937 (  database_to_xmlschema       PGNSP PGUID 12 100 0 f f t f s 3 142 "16 16 25" _null_ _null_ "{nulls,tableforest,targetns}" database_to_xmlschema - _null_ ));
+DESCR("map database structure to XML Schema");
+DATA(insert OID = 2938 (  database_to_xml_and_xmlschema PGNSP PGUID 12 100 0 f f t f s 3 142 "16 16 25" _null_ _null_ "{nulls,tableforest,targetns}" database_to_xml_and_xmlschema - _null_ ));
+DESCR("map database contents and structure to XML and XML Schema");
+
 DATA(insert OID = 2931 (  xmlpath      PGNSP PGUID 12 1 0 f f f f i 3 143 "25 142 1009" _null_ _null_ _null_ xmlpath - _null_ ));
 DESCR("evaluate XPath expression, with namespaces support");
 DATA(insert OID = 2932 (  xmlpath      PGNSP PGUID 14 1 0 f f f f i 2 143 "25 142" _null_ _null_ _null_ "select pg_catalog.xmlpath($1, $2, NULL)" - _null_ ));

src/include/utils/xml.h

@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2007, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/utils/xml.h,v 1.17 2007/03/22 20:14:58 momjian Exp $
+ * $PostgreSQL: pgsql/src/include/utils/xml.h,v 1.18 2007/04/01 09:00:26 petere Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -47,6 +47,14 @@ extern Datum cursor_to_xmlschema(PG_FUNCTION_ARGS);
 extern Datum table_to_xml_and_xmlschema(PG_FUNCTION_ARGS);
 extern Datum query_to_xml_and_xmlschema(PG_FUNCTION_ARGS);
 
+extern Datum schema_to_xml(PG_FUNCTION_ARGS);
+extern Datum schema_to_xmlschema(PG_FUNCTION_ARGS);
+extern Datum schema_to_xml_and_xmlschema(PG_FUNCTION_ARGS);
+
+extern Datum database_to_xml(PG_FUNCTION_ARGS);
+extern Datum database_to_xmlschema(PG_FUNCTION_ARGS);
+extern Datum database_to_xml_and_xmlschema(PG_FUNCTION_ARGS);
+
 typedef enum
 {
 	XML_STANDALONE_YES,