Author: shawkins Date: 2010-11-23 16:23:39 -0500 (Tue, 23 Nov 2010) New Revision: 2739 Added: trunk/documentation/reference/src/main/docbook/en-US/content/updatable_views.xml Modified: trunk/build/kits/jboss-container/teiid-releasenotes.html trunk/documentation/reference/src/main/docbook/en-US/Reference.xml Log: TEIID-1349 adding docs for updatable views Modified: trunk/build/kits/jboss-container/teiid-releasenotes.html =================================================================== --- trunk/build/kits/jboss-container/teiid-releasenotes.html 2010-11-23 20:30:27 UTC (rev 2738) +++ trunk/build/kits/jboss-container/teiid-releasenotes.html 2010-11-23 21:23:39 UTC (rev 2739) @@ -27,6 +27,7 @@ <H2><A NAME="Highlights"></A>Highlights</H2> <UL> <LI><B>Subquery Optimization</B> - added rewrite to INNER JOIN for applicable WHERE clause subqueries. Also added cost based SEMI and ANTI-SEMI join handling for applicable non-pushed WHERE and HAVING subqueries. + <LI><B>Updatable Views</B> - added support to perform simple pass-through and more complicated updates through views by default. </UL> <h2><a name="Compatibility">Compatibility Issues</a></h2> Modified: trunk/documentation/reference/src/main/docbook/en-US/Reference.xml =================================================================== --- trunk/documentation/reference/src/main/docbook/en-US/Reference.xml 2010-11-23 20:30:27 UTC (rev 2738) +++ trunk/documentation/reference/src/main/docbook/en-US/Reference.xml 2010-11-23 21:23:39 UTC (rev 2739) @@ -51,6 +51,7 @@ <xi:include href="content/xml_queries.xml" xmlns:xi="http://www.w3.org/2001/XInclude" /> <xi:include href="content/datatypes.xml" xmlns:xi="http://www.w3.org/2001/XInclude" /> <xi:include href="content/scalar_functions.xml" xmlns:xi="http://www.w3.org/2001/XInclude" /> + <xi:include href="content/updatable_views.xml" xmlns:xi="http://www.w3.org/2001/XInclude" /> <xi:include href="content/procedures.xml" xmlns:xi="http://www.w3.org/2001/XInclude" /> <xi:include href="content/transaction_support.xml" xmlns:xi="http://www.w3.org/2001/XInclude" /> <xi:include href="content/dataroles.xml" xmlns:xi="http://www.w3.org/2001/XInclude" /> Added: trunk/documentation/reference/src/main/docbook/en-US/content/updatable_views.xml =================================================================== --- trunk/documentation/reference/src/main/docbook/en-US/content/updatable_views.xml (rev 0) +++ trunk/documentation/reference/src/main/docbook/en-US/content/updatable_views.xml 2010-11-23 21:23:39 UTC (rev 2739) @@ -0,0 +1,57 @@ +<?xml version="1.0" encoding="UTF-8"?> +<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd" [ +<!ENTITY % CustomDTD SYSTEM "../../../../../../docbook/custom.dtd"> +%CustomDTD; +]> +<chapter id="updatable_views"> + <title>Updatable Views</title> + + <para>Any view may be marked as updatable. In many circumstances the view definition may allow the view to be inherently + updatable without the need to manually define handing of INSERT/UPDATE/DELETE operations.</para> + + <para>An inherently updatable view cannot be defined with a query that has:</para> + + <itemizedlist> + <listitem> + <para>A set operation (INTERSECT, EXCEPT, UNION, UNION ALL)</para> + </listitem> + <listitem> + <para>SELECT DISTINCT</para> + </listitem> + <listitem> + <para>Aggregation (aggregate functions, GROUP BY, HAVING)</para> + </listitem> + <listitem> + <para>A LIMIT clause</para> + </listitem> + </itemizedlist> + + <para>Any view column that is not mapped directly to a column is not updatable and cannot be targeted by an UPDATE set + clause or be an INSERT column.</para> + + <para>If a view is defined by a join query or has a WITH clause it may still be inherently updatable. However in these situations there + are further restrictions and the resulting query plan may execute multiple statements. + For a non-simple query to be updatable, it is required:</para> + + <itemizedlist> + <listitem> + <para>An INSERT/UPDATE can only modify a single <xref linkend="key_preserved_table"/>.</para> + </listitem> + <listitem> + <para>To allow DELETE operations there must be only a single <xref linkend="key_preserved_table"/>.</para> + </listitem> + </itemizedlist> + + <para>If the default handling is not available or you wish to have an alternative implementation of an INSERT/UPDATE/DELETE, + then you may use <xref linkend="update_procedures"/> to define procedures to handle the respective operations.</para> + + <section id="key_preserved_table"> + <title>Key-preserved Table</title> + + <para>A key-preserved table has a primary or unique key that would remain unique if it were projected into the result of the query. + Note that it is not actually required for a view to reference the key columns in the SELECT clause. + The query engine can detect a key preserved table by analyzing the join structure - which is currently required to be in ANSI join form. + The engine will ensure that a join of a key-preserved table must be against one of its foreign keys.</para> + </section> + +</chapter> \ No newline at end of file Property changes on: trunk/documentation/reference/src/main/docbook/en-US/content/updatable_views.xml ___________________________________________________________________ Name: svn:mime-type + text/plain